GLYCOLIC ACID

GLYCOLIC ACID

GLYCOLIC ACID

Glycolic acid is a natural organic acid, also called alpha-hydroxy acids (AHA). 
Glycolic acid is usually made from sugar cane. 
Glycolic acid is used in mild peels and acid-based exfoliators. 
Glycolic acid accelerates the loss of dead cells and promotes cell renewal. 
Like other fruit acids, Glycolic acid is also used to smooth wrinkles, lighten the complexion, fade pigments and irregularities of the skin.

EC / List no.: 201-180-5
CAS no.: 79-14-1

IUPAC name
2-Hydroxyethanoic acid
Preferred IUPAC name
hydroxyacetic acid
Other names
dicarbonous acid
glycolic acid
hydroacetic acid

Name: Glycolic acid
Synonyms    
Hydroxyacetic acid
glycollic acid
Hydroxyethanoic acid
2-hydroxyacetate
Total acid
AHA-glycolic acid

Applications
Glycolic acid is used in the textile industry as a dyeing and tanning agent, in food processing as a flavoring agent and as a preservative, and in the pharmaceutical industry as a skin care agent. 
It is also used in adhesives and plastics. 
Glycolic acid is often included in emulsion polymers, solvents and additives for ink and paint in order to improve flow properties and impart gloss. 
It is used in surface treatment products that increase the coefficient of friction on tile flooring. 
It is the active ingredient in the household cleaning liquid PineSol.

Skin care
Due to its capability to penetrate skin, glycolic acid finds applications in skin care products, most often as a chemical peel. 
Physicianstrength peels can have a pH as low as 0.6 (strong enough to completely keratolyze the epidermis), while acidities for home peels can be as low as 2.5. 
Once applied, glycolic acid reacts with the upper layer of the epidermis, weakening the binding properties of the lipids that hold the dead skin cells to­gether. 
This allows the stratum corneum to be exfoliated, exposing live skin cells.

Safety
Glycolic acid is a strong irritant depending on pH.
Like ethylene glycol, it is metabolized to oxalic acid, which could make it dangerous if ingested.

Organic synthesis
Glycolic acid is a useful intermediate for organic synthesis, in a range of reactions including: oxidationreduction, esterification and long chain polymerization. 
It is used as a monomer in the preparation of polyg­ly­colic acid and other biocompatible copolymers (e.g. PLGA). 
Commercially, important derivatives include the methyl (CAS# 96-35-5) and ethyl (CAS# 623-50-7) esters which are readily distillable (boiling points 147–149 °C and 158–159 °C, respectively), unlike the parent acid. 
The butyl ester (b.p. 178–186 °C) is a component of some varnishes, being desirable because it is nonvolatile and has good dissolving properties.

Agriculture
Many plants make glycolic acid during photorespiration. 
Its role consumes significant amounts of energy. 
In 2017 researchers announced a process that employs a novel protein to reduce energy consumption/loss and prevent plants from releasing harmful ammonia. 
The process converts glycolate into glycerate without using the conventional BASS6 and PLGG1 route

Glycolic acid is a 2-hydroxy monocarboxylic acid that is acetic acid where the methyl group has been hydroxylated. 
Glycolic acid has a role as a metabolite and a keratolytic drug. 
Glycolic acid is a 2-hydroxy monocarboxylic acid and a primary alcohol. 
Glycolic acid derives from an acetic acid. 
Glycolic acid is a conjugate acid of a glycolate.

Glycolic acid (hydroacetic acid or hydroxyacetic acid); chemical formula C2H4O3 (also written as HOCH2CO2H), is the smallest α-hydroxy acid (AHA). 
This colorless, odorless, and hygroscopic crystalline solid is highly soluble in water. 
Glycolic acid is used in various skin-care products. 
Glycolic acid is found in some sugar-crops.

A glycolate or glycollate is a salt or ester of glycolic acid.

Glycolic Acid, the most common alpha hydroxide acid (AHA), stimulates new growth of skin, collagen and elastin. 
As well as working to diminish brown spots and hyperpigmentation, it also reduces fine lines, wrinkles, acne, scars and other signs of ageing.

Glycolic Acid Brightening Solution prevents dead cells from clumping together, thus increasing cell turnover. 
The skin appears bright and rejuvenated, reflecting a healthy glow.

Glycolic Acid is the most commonly used form of Alpha Hydroxy Acids (AHAs), which are a group of naturally occurring acids derived from certain plants and fruits.

Glycolic Acid is considered to decrease the stratum corneum barrier and increase the penetration of topical agents; it works by stimulating new growth of skin and collagen and has an exfoliant action, once applied glycolic acid reacts with the upper layer of the epidermis, weakening the binding properties of the lipids that hold the dead skin cells together. Furthermore it stimulates glycos-aminos-glycans like hyaluronic acid. The result is a much-smoother skin surface and a more youthful appearance.

Another benefit is glycolic acid’s ability to draw moisturizers into the newly-exfoliated skin surface. 
Glycolic Acid reduces the appearance of fine lines and wrinkles, age spots as well as improves sun-damaged skin. 
When used in combination with polyvitamins, Glycolic Acid is also useful for reducing stretch marks.

Glycolic acid is a natural constituent of sugar cane and normalizes the skin’s exfoliation process refining the appearance of pore size and smoothing the look of fine lines and wrinkles as it re-texturizes skin

Alpha hydroxy acids, or AHAs, have long been known to be excellent additions to every skincare routine, but when you see these ingredients on product labels, you may not immediately recognize them. Glycolic acid, which is one of the five AHAs, is arguably the most common of this group for its use in skincare products

Glycolic acid is one of the alpha hydroxy acids. Glycolic acid is derived from sugar cane and is the smallest molecule of the five AHAs.

Along with lactic acid, citric acid, malic acid, and tartaric acids, glycolic acid is one of the alpha hydroxy acids. 
These ingredients are naturally-occurring, although they can also be created synthetically. 
Glycolic acid is derived from sugar cane and is the smallest molecule of the five AHAs. 
Because of this quality, it can penetrate the skin with ease, making it an excellent addition to skincare products aimed at improving the appearance of skin discoloration and dullness.

Synonyms     
2-Hydroxyacetic acid    
2-Hydroxyethanoic acid    
α-hydroxyacetic acid    
alpha-Hydroxyacetic acid    
Glycolic acid    
GLYCOLIC ACID    
Glycollic acid    
HOCH2COOH    
Hydroxyacetic acid    
Hydroxyethanoic acid

Glycolic acid has the ability to help remove dead cells from the surface of the skin and stimulate the regeneration of new ones.
As a result, it significantly improves the appearance of the skin, reducing blemishes and scars, wrinkles and imperfections and adding radiance and vitality to the face.

Glycolic Spray is a professional peeling based on Glycolic Acid, an active with a keratolytic and exfoliating action. The concentration of the acid in free form enables an efficient peeling effect in a short time.

ACTIVE INGREDIENTS
Glycolic acid – Also called hydroxyacetic acid, it is the smallest and best known among the alpha-hydroxy acids. 
It has no colour nor smell and is highly soluble in water. 
Although it may be created through a chemical reaction, it can be classified as a natural product because it is extracted from the fruit (pineapple, sugar cane, sugar beet, unripe grapes and melon). 
Thanks to its great solubility and acidity, the glycolic acid is a perfect exfoliating active. It penetrates into the dermis, weakening the lipids of the dead skin and promoting their expulsion.

While a couple of ingredients are being hailed as miracle agents in the skincare industry, one consistent winner getting maximum mentions by dermatologists is glycolic acid. A plant-derived active ingredient, glycolic acid can address a tide of skin issues from acne to pigmentation and aging.

Additionally, using glycolic acid with other skincare products can help to increase the effectiveness of those products by exfoliating the skin’s surface,

Primarily, glycolic acid is a skin retexturizing ingredient, working to sweep away the outer layer of dead skin cells to reveal the fresh, revitalized skin underneath. Glycolic acid may also help to reduce the appearance of acne scars, blemishes, age spots and large pores by aiding in cell turnover.

Additionally, using glycolic acid with other skincare products can help to increase the effectiveness of those products by exfoliating the skin’s surface, which may help topical products to fully penetrate (American Academy of Dermatology).

For a soothing effect, ingredients such as allantoin glycyrrhetinic acid, bisabolol and portulaca extract work alongside glycolic acid and the retinoid to provide a sensation of calmness.

Glycolic acid skincare products come in many different forms, but for a more comprehensive anti-aging strategy, it may be most effective when paired with other anti-aging ingredients as well.

Glycolic acid is a powerhouse ingredient in many skin care products. 
From anti-aging to moisturizing, hyperpigmentation to dullness, glycolic acid treats a number of skin care issues, all without causing dryness or irritating sensitive skin. 

But what exactly is glycolic acid, and what are the best glycolic acid products you can add to your skin care routine? 
We answer these questions and more in your ultimate guide to everything glycolic acid.

So What is Glycolic Acid?
Glycolic acid is an alpha-hydroxy acid (or AHAs) derived from sugarcane. 
The smallest of all the AHAs, glycolic acid is in the same league as other powerful skin care ingredients, like lactic acid and citric acid. 
Because it’s so small and has such a low molecular weight, glycolic acid can actually penetrate your skin’s barrier and go deeper than other acids.

So, what does this mean for your skin? 
Well, it’s awesome when it comes to exfoliating, because glycolic acid can slough away dead skin cells like nothing else to reveal your inner glow.

Okay, So What Exactly Does Glycolic Acid Do?
Because of glycolic acid’s incredible exfoliating properties, it’s found in a variety of exfoliators and chemical peels. 
But glycolic acid has other skin superpowers, too. 
Fine lines? No problem. Discoloration? 
Not to worry–glycolic acid stimulates collagen production, which makes your skin look and feel firmer while also fighting visible signs of sun damage and aging. 

In fact, whether you have acne and clogged pores, or want to soothe dry skin or dullness, glycolic acid is your one-stop stop for radiant, even-toned skin. 
And, because it’s so lightweight, it’s less likely than other skin care acids (like salicylic acid or benzoyl peroxide) to cause irritation for sensitive skin types.

GLYCOLIC ACID
THE GOLD STANDARD FOR GLOWING SKIN
Lauded as the gold standard in chemical exfoliation, glycolic acid is the smallest alpha hydroxy acid (AHA). This potent ingredient is recognized for its ability to provide an even exfoliation to the skin by helping promote cellular turnover for improvement in the look of fine lines, skin texture, tone, and radiance. 
Available in cleansers, serums, toners, or creams, SkinCeuticals glycolic acid formulas provide an effective solution for various skin concerns including dullness, uneven texture and tone, blemishes, and or signs of skin aging.

Glycolic acid-based chemical peel that removes dead cells and promotes their renewal. 
Leaves skin soft and velvety. Ideal for fighting the signs of aging, skin blemishes and imperfections.

It is important to know the ingredients contained in your cosmetics when buying them and to optimize their use in order to achieve the results you expect from them. 

Glycolic acid is the most popular of the AHAs, as it has a very small molecular chain that allows it to penetrate into different layers of the skin, deeper or more superficial, depending on its concentration. In low concentrations it has moisturising properties and in high concentrations it is a powerful exfoliant.
Glycolic acid has the ability to help remove dead cells from the surface of the skin and stimulate the regeneration of new ones.
As a result, it significantly improves the appearance of the skin, reducing blemishes and scars, wrinkles and imperfections and adding radiance and vitality to the face.

Glycolic acid is a naturally occurring substance, that when used in skincare products offers many benefits to the skin, from rejuvenating to moisturizing. In its raw state, glycolic acid is a powder made up of colorless crystals that have no scent. 

Glycolic Acid and Lactic Acid are naturally occuring organic acids also known as Alpha Hydroxy Acids or AHAs. 
The salts of Glycolic Acid (Ammonium Glycolate, Sodium Glycolate), the salts of Lactic Acid (Ammonium Lactate, Calcium Lactate, Potassiu Lactate, Sodium Lactate, TEA-Lactate) and the esters of Lactic Acid (Methyl Lactate, Ethyl Lactate, Butyl Lactate, Lauryl Lactate, Myristyl Lactate, Cetyl Lactate) may also be used in cosmetics and personal care products. 
In cosmetics and personal care products, these ingredients are used in the formulation of moisturizers, cleansing products, and other skin care products, as well as in makeup, shampoos, hair dyes and colors and other hair care products.

Why is it used in cosmetics and personal care products?
The following functions have been reported for Glycolic Acid, Lactic Acid and their salts and esters.

Buffering agent – Ammonium Lactate, Potassium Lactate, Sodium Lactate
Cosmetic astringent – Calcium Lactate
Exfoliant – Glycolic Acid, Lactic Acid, Ammonium Glycolate, Ammonium Lactate, Calcium Lactate, Potassium Lactate, Sodium Lactate
Humectant – Lactic Acid
pH adjuster – Glycolic Acid, Lactic Acid, Ammonium Glycolate, Sodium Glycolate
Skin conditioning agent – emollient – Lauryl Lactate, Myristyl Lactate, Cetyl Lactate
Skin conditioning agent – humectant – Lactic Acid, Ammonium Lactate, Potassium Lactate, Sodium Lactate, TEA-Lactate
Skin conditioning agent – miscellaneous – Lactic Acid
Solvent – Methyl Lactate, Ethyl Lactate, Butyl Lactate
Scientific Facts: 
Glycolic Acid and Lactic Acid are alpha hydroxy acids (AHAs). 
They may be either naturally occurring or synthetic. 
They are often found in products intended to improve the overall look and feel of the skin. 
Glycolic acid is the most widely used of out of the group and is usually manufactured from sugar cane. 
Lactic acid, derived primarily from milk and its origins can be traced back to Cleopatra, who purportedly used sour milk on her skin.

When it comes to exfoliating your face, glycolic acid is up there as one of the best of the bunch
A type of alpha-hydroxy-acid (or AHA), glycolic acid gently removes the outer most layer of dead skin cells revealing a brighter, fresher looking complexion. 
A gold-standard in skincare, discover its benefits with our range of tonics, cleansing pads, ampules and more.

Glycolic acid (Hydroxyacetic acid) is an α-hydroxy acid. 
Glycolic acid solutions having concentration of 70% and pH range of 0.08 to 2.75 are widely employed as superficial chemical peeling agents.
Various oligomers or polymers of lactic and/or glycolic acid (low molecular weight) have been prepared.
Glycolic acid can be determined via plant tissue coupled flow injection chemiluminescence biosensors, which can be used both as a plant-tissue based biosensor and chemiluminescence flow sensor.[4][5]

Application
Glycolic acid (Hydroxyacetic acid) has been used in the preparation of PLGA-PEG-PLGA copolymer (PLGA = poly(lactic/glycolic, PEG = polyethylene glycol).

Unless you have avoided every bit of skin care info out there so far (in this case special welcome to you! :)) you must have heard of glycolic acid. 
Or at least about AHAs or to put it even more nice-sounding fruit acids. 

AHAs (alpha-hydroxy acids) stand for a whole group of ingredients and glycolic acid is one of them. 
If you are a chemist geek type you might want to know that the point of AHAs is that they contain a hydroxy group (-OH) and a carboxylic acid part (HO¬ =0) and these two parts are only one carbon apart (if they are two carbons apart it’s a beta-hydroxy acid).

It’s the most researched AHA with the most proven skin benefits
It gently lifts off dead skin cells to reveal newer, fresher, smoother skin
It can help skin’s own collagen production that results in firmer, younger skin
It can fade brown spots caused by sun damage or PIH
Choose a product where you know the concentration and pH value because these two greatly influence effectiveness
Don’t forget to use your sunscreen (in any case but especially so next to an AHA product)
Slight stinging or burning with a stronger AHA product is normal
If your skin is very sensitive, rosacea prone choose rather a BHA or PHA product

In its earliest incarnation, glycolic acid was a totally natural ingredient derived from sugar cane. 
These days, however, manufacturers often make it synthetically. 
Regardless of the manufacturing method, glycolic acid falls into a category of effective active compounds known as alpha hydroxy acids (AHAs). 
According to dermatology expert Dr. Heather Brannon, these acids come in five different types:

Glycolic acid, from sugar cane
Lactic acid, from milk
Citric acid, from oranges and lemons
Malic acid, from apples and pears
Tartaric acids, from grapes
Glycolic acid is the most commonly used alpha hydroxy acid, owing to its reputation as one of the safest and most effective. 
Its molecules are the smallest among the AHAs, so it’s able to penetrate skin better and be absorbed readily.

It works by actually destroying the bonds between old skin cells, freeing them so they can be sloughed off. 
This might sound scary and counterproductive, but it’s actually quite beneficial.

Glycolic Acid Skin Benefits
Glycolic acid is an exfoliator, which means that it safely removes the outer layer of dead skin cells. 
In this way, it helps accelerate your skin’s renewal process, bringing fresh, new skin to the surface on a regular basis when used routinely. This can help your skin look younger and dewier, with a glow that arises from increased circulation and faster cell turnover.

It’s much more than anti-aging product, though; glycolic acid also helps lighten discolorations such as sun and age spots. 
It can even help skin that’s prone to blackheads, whiteheads, and acne by keeping pores clear of old skin that tends to clog them and cause problems.

WHAT IS GLYCOLIC ACID USED FOR?
Primarily, glycolic acid is used for getting rid of dead skin cells. It’s also popular for its exfoliating properties, making it beneficial for un-clogging pores and thoroughly cleansing your face.

WHAT DOES GLYCOLIC ACID DO, EXACTLY?
As a chemical exfoliant, glycolic acid breaks down the substance that holds dead skin cells together. 
While some skin treatments cleanse the upper layer of your skin, glycolic acid penetrates deeper and un-clogs your pores from their base level.
This process of ‘waking up’ the skin leads to higher cell turnover and more youthful looking skin. 

HOW DOES GLYCOLIC ACID COMPARE TO OTHER CHEMICAL EXFOLIANTS?
Compared to, say, salicylic acid, glycolic acid can be a little harsh. While glycolic acid peels were once at go-to for facialists, they’ve since fallen in popularity.
Instead, other popular, at-home products involving glycolic acid have become readily available on the market, including cleansers, toners and pads. 
While still good for your skin, these products involve a lower concentration of glycolic acid, so as to avoid damaging and wearing out your skin.

There’s nothing like adding alpha hydroxy acids (AHAs) and their cousin, beta hydroxy acid (BHA, also known as salicylic acid), to your morning and/or nighttime routine. 
Whether used as the key ingredient in a powerful once-a-week, overnight peel or as an adjunct to make a great self-tan work even better, AHAs and BHA are powerfully effective compounds that fit easily into a clean and nontoxic skin-care regimen for noticeable results.

Glycolic, lactic, citric, and malic acids all fall under the exfoliating AHA category and work by gently removing the top layer of dead skin cells (along with pollution, grime, makeup, and anything else that might potentially clog pores) through a natural chemical exfoliation. 
Salicylic acid works in a similar manner. The advantage of chemical exfoliation is that it’s extremely even, unlike a physical exfoliation, with a gritty scrub or the rough surface of a washcloth, which can cause microtears in skin. 
The results are the reason AHAs are so beloved by so many different skin types: They can help unclog pores, soften the appearance of wrinkles, and minimize the visibility of dark spots, and they can even help increase moisture in skin. After a good exfoliation with AHAs, your skin should be soft and smooth and look decidedly glowier.

Like all exfoliants, AHAs and salicylic acid facilitate the absorption of any treatment that follows. 
Different types of acids yield different benefits, so it’s often useful to combine them in skin treatments. 
Glycolic, for instance, is the smallest molecule among the alpha hydroxy acids, so it can go deeper into the layers of the skin; it was initially developed for the treatment of extremely dry skin. Salicylic acid (which is the same compound as aspirin) has soothing properties, so it can be helpful for breakout-prone skin.

The concentrations of a particular acid within a formula can make a big difference in results: At lower concentrations, AHAs can be gentle enough for even sensitive skin. At higher concentrations, like the 15% glycolic acid in the new GOOPGLOW Overnight Glow Peel, they can work powerfully to retexturize, smooth, clarify, and refine.

Whether you’re dealing with dryness, sun damage, blemishes, or dullness or you just want your beautiful skin to continue to be beautiful as you age, AHAs and BHA are a brilliant way to improve your skin in both the short and long term, without potentially toxic ingredients. 
The formulas below are all infused with alpha or beta hydroxy acids; pick and choose the best regimen for your skin’s needs (if you have sensitive skin, err on the side of caution when you’re using any exfoliating acids), then stick with it, and you should see a major difference in your skin.

History
The name “glycolic acid” was coined in 1848 by French chemist Auguste Laurent (1807–1853). 
He proposed that the amino acid glycine—which was then called glycocolle—might be the amine of a hypothetical acid, which he called “glycolic acid” (acide glycolique).

Glycolic acid was first prepared in 1851 by German chemist Adolph Strecker (1822–1871) and Russian chemist Nikolai Nikolaevich Sokolov (1826–1877). 
They produced it by treating hippuric acid with nitric acid and nitrogen dioxide to form an ester of benzoic acid and glycolic acid (C6H5C(=O)OCH2COOH), which they called “benzoglycolic acid” (Benzoglykolsäure; also benzoyl glycolic acid). 
They boiled the ester for days with dilute sulfuric acid, thereby obtaining benzoic acid and glycolic acid (Glykolsäure).

IUPAC name: 2-Hydroxyethanoic acid
Preferred IUPAC name: hydroxyacetic acid

Other names
dicarbonous acid
glycolic acid
hydroacetic acid

CAS Number: 79-14-1 

Glycolic acid, a type of alpha-hydroxy acid, is a chemical exfoliator that battles both acne and wrinkles. It’s also effective at reducing dark spots and evening skin tone.

Preparation
Glycolic acid can be synthesized in various ways. 
The predominant approaches use a catalyzed reaction of formaldehyde with synthesis gas (carbonylation of formaldehyde), for its low cost.

It is also prepared by the reaction of chloroacetic acid with sodium hydroxide followed by re-acidification.

Other methods, not noticeably in use, include hydrogenation of oxalic acid, and hydrolysis of the cyanohydrin derived from formaldehyde.
Some of today’s glycolic acids are formic acid-free. 
Glycolic acid can be isolated from natural sources, such as sugarcane, sugar beets, pineapple, cantaloupe and unripe grapes.

Glycolic acid can also be prepared using an enzymatic biochemical process that may require less energy.

Properties
Glycolic acid is slightly stronger than acetic acid due to the electron-withdrawing power of the terminal hydroxyl group. 
The carboxylate group can coordinate to metal ions forming coordination complexes. 
Of particular note are the complexes with Pb2+ and Cu2+ which are significantly stronger than complexes with other carboxylic acids. 
This indicates that the hydroxyl group is involved in complex formation, possibly with the loss of its proton.

Applications
Glycolic acid is used in the textile industry as a dyeing and tanning agent,in food proce ssing as a flavoring agent and as a preservative, and in the pharmaceutical industry as a skin care agent. 
It is also used in adhesives and plastics.
Glycolic acid is often included in emulsion polymers, solvents and additives for ink and paint in order to improve flow properties and impart gloss. 
It is used in surface treatment products that increase the coefficient of friction on tile flooring. 
It is the active ingredient in the household cleaning liquid Pine-Sol.

Glycolic Acid is an alpha hydroxy acid that exfoliates the skin. 
This 7% toning solution offers mild exfoliation for improved skin radiance and visible clarity. 
The formula also improves the appearance of skin texture with continued use.

This formula contains a studied Tasmanian Pepperberry derivative to help reduce irritation associated with acid use. 
This derivative is of plant origin and varies in colour seasonally and this colour variation may be apparent in the formula from time to time. 
The formula is further supported with inclusion of ginseng root and aloe vera for both visible radiance and soothing benefits.

Contraindications: This formula should not be used on sensitive, peeling or compromised skin. 
Please refer to additional sun protection note and other warnings in provided Directions.

This pH of this formula is approximately 3.6. 
Glycolic Acid has a pKa of 3.6 and pKa is the most important aspect to consider in formulating with acids. 
pKa implies acid availability. When pKa is close to pH, there is an ideal balance between salt and acidity, maximizing effectiveness of the acid and reducing irritation. 
Higher pH numbers in such a case would increase salt which counter-intuitively would make the formula even more irritating than if the formula was more acidic.

Note: While exfoliating acids can result in quick visible benefits, we generally suggest indirect forms of skin exfoliation in favour of direct forms such as this formula due to potential inflammation and sensitivity associated with acids. 
Please refer to NIOD’s Non-Acid Acid Precursor for such a reference.

Glycolic acid, like other AHAs, acts on the surface layer of the skin to dissolve the ‘cement’ between dead cells. 
It therefore gently resurfaces skin without the need for scrubbing. 
This is why acid-based products are often referred to as ‘chemical exfoliators’, in contrast to traditional, grit-based ‘physical exfoliators’, which are now largely regarded as the inferior option.

AHAs are water soluble, so they work well on the superficial skin layers, which we call the epidermis. 
Glycolic acid has been shown in studies to have dermal influence, boosting collagen-remodelling cells (which helps to reduce the appearance of fine lines and wrinkles), and melanocyte-stabilising properties, meaning it works well for pigmentation, too. 
It’s a versatile multi-tasker.

The process works by loosening and dissolving the glue-like substance called the desmosome, which holds old skin cells together.
As they get to work, you often feel a tingle in the skin. 
Once the desmosome is broken down, the skin naturally sheds its old, dead skin cells. 
So, although you won’t actually see your skin exfoliating, you’ll soon see and feel the smoother textured, more radiant-looking skin.

Skin care

This section needs more medical references for verification or relies too heavily on primary sources. 
Please review the contents of the section and add the appropriate references if you can. 
Unsourced or poorly sourced material may be challenged and removed.

Due to its capability to penetrate skin, glycolic acid finds applications in skin care products, most often as a chemical peel. 
Physician-strength peels can have a pH as low as 0.6 (strong enough to completely keratolyze the epidermis), while acidities for home peels can be as low as 2.5. 
Once applied, glycolic acid reacts with the upper layer of the epidermis, weakening the binding properties of the lipids that hold the dead skin cells together. 
This allows the stratum corneum to be exfoliated, exposing live skin cells.

Organic synthesis
Glycolic acid is a useful intermediate for organic synthesis, in a range of reactions including: oxidation-reduction, esterification and long chain polymerization. 
It is used as a monomer in the preparation of polyglycolic acid and other biocompatible copolymers (e.g. PLGA). 
Commercially, important derivatives include the methyl (CAS# 96-35-5) and ethyl (CAS# 623-50-7) esters which are readily distillable (boiling points 147–149 °C and 158–159 °C, respectively), unlike the parent acid. 
The butyl ester (b.p. 178–186 °C) is a component of some varnishes, being desirable because it is nonvolatile and has good dissolving properties.

Agriculture
Many plants make glycolic acid during photorespiration. 
Its role consumes significant amounts of energy. In 2017 researchers announced a process that employs a novel protein to reduce energy consumption/loss and prevent plants from releasing harmful ammonia. 
The process converts glycolate into glycerate without using the conventional BASS6 and PLGG1 route.

Safety
Glycolic acid is a strong irritant depending on pH.
Like ethylene glycol, it is metabolized to oxalic acid, which could make it dangerous if ingested.

Glycolic acid is a colorless, odorless alpha-hydroxy-acid (AHA) derived from sugarcane. 
Glycolic acid is a type of chemical exfoliant that dissolves the bonds between dead skin cells, allowing them to be wiped away easily, revealing smooth, younger skin.

Glycolic acid is a type of alpha-hydroxy acid (or AHA) that’s derived from sugar cane. 

Glycolic acid joins other acids you might recognize, such as lactic acid (derived from sour milk and purportedly a favorite of Cleopatra’s), tartaric acid (from grapes), and citric acid—which, you might guess, comes from citrus fruits.

It’s actually the smallest naturally occurring alpha-hydroxy-acid.

That means Glycolic can penetrate the skin more deeply and easily compared to other alpha hydroxy acids you might know, like lactic acid, which is why it is so commonly used.

Alpha-hydroxy-acids like glycolic acid are water soluble, which means they dissolve in water. 
On the other hand, beta-hydroxy-acids (BHAs), such as salicylic acid, are oil soluble, meaning they dissolve in oil and can penetrate deeper into oily pores.

But that doesn’t mean AHAs aren’t effective. If used correctly, as in a glycolic acid peel, they can be an easy way to get smoother, glowing skin.

Do your skin concerns include managing hyperpigmentation or fending off fine lines and wrinkles? 
If yes, then a glycolic acid peel might be the treatment for you. 
Because it’s a powerful exfoliant, it can visibly reduce signs of aging and hyperpigmentation by weakening the connections between the cells in the top layer of the skin, which helps remove the dead skin cells, giving the skin a refreshed look and a glowing complexion.

More specifically, glycolic acid reacts readily with the upper layer of the skin, weakening the binding properties of the lipids that hold the dead skin cells together through a process called desquamation. 
That allows the outer skin to dissolve, subsequently revealing the underlying skin.

These effects can be used to reduce the appearance of wrinkles, sunspots, melasma, and acne scars.

When it comes to managing melasma, glycolic acid can be used to suppress the formation of melanin pigment in the skin. 
It does so by inhibiting the actions of tyrosinase, an enzyme that normally speeds up the complex process by which the pigment melanin is produced by certain types of skin cells. 
Slowing this process down results in less hyperpigmentation. 
But don’t expect to see results straight away; it normally takes between four and eight treatments before you see a significant difference.

There’s some research to show that glycolic acid has antibacterial effects on P. acnes, the bacteria responsible for inflammatory acne.

However, if you have sensitive skin or a condition like psoriasis, rosacea, or eczema, is it essential to speak with a board-certified dermatologist prior to any chemical peels. 
Glycolic acid tends to be more irritating than other chemical exfoliants, so you may need to choose a different acid or figure out a different treatment option.

It’s also important to avoid doing a peel if you have a sunburn or active skin infection. 
And if you’re taking any prescription medications for your acne, you should talk about that with your dermatologist before doing a peel, as these can also irritate your skin.

The major advantage of glycolic acid is that it does more than treat breakouts. The ingredient can also tackle hyperpigmentation, dullness, and signs of skin aging, such as lines and wrinkles, without breaking a sweat

First and foremost, glycolic acid is an exfoliant. 
It helps shed dead skin cells and reveal the newer, brighter layers underneath by acting on the stratum corneum (the outermost layer of skin). 
“Normal, intact stratum corneum consists of tightly packed layers of dead skin cells that are tightly bonded together

“Glycolic acid loosens these bonds.” With their glue dissolved by glycolic acid, those tough, rough layers of dead skin cells can more easily slough away.

But because glycolic acid is so small, it can get deeper into your skin too, where it does some serious work. 
Glycolic acid stimulates fibroblasts in the dermis to produce increased amounts of collagen.

And by stimulating collagen production, it helps skin feel firmer and minimizes fine lines and wrinkles. 
Between the superficial action on your stratum corneum and the work it does below, your skin will feel smoother and look more radiant and even-toned.

Glycolic acid is a water-soluble alpha hydroxy acid (AHA) that is derived from sugar cane. 
It is one of the most well-known and widely used alpha-hydroxy acids in the skincare industry. Other alpha-hydroxy acids include lactic acid, malic acid, tartaric acid, and citric acid.

How Glycolic Acid Works
Glycolic acid has the smallest sized molecules of all the alpha-hydroxy acids.1

 Because of these super tiny molecules, glycolic acid can easily penetrate the skin. This allows glycolic acid to exfoliate the skin more effectively than other AHAs.

It works by speeding up cell turnover.
It helps dissolve the bonds that hold skin cells together, allowing dead skin cells to slough off more rapidly than they would on their own.

Glycolic acid also stimulates your skin to create more collagen.
Collagen is the protein that gives skin its firmness, plumpness, and elasticity. (Collagen is also the protein that gives strength to your bones and connective tissues.)

As you age, collagen production naturally slows down. 
It’s also destroyed by excessive sun exposure. Using glycolic acid regularly can help prevent this breakdown of collagen.

What It Does for Your Skin
Glycolic acid is an incredibly popular treatment because of the many benefits it has for the skin. 
It has effective skin-renewing properties, so it is often used in anti-aging products. 
It can help smooth fine wrinkles and improve the skin’s tone and texture.
 Glycolic acid plumps the skin and helps boost hydration levels.

It’s not just an anti-aging treatment, though. Glycolic acid can also help fight sun damage. 
It’s often used to fade minor fade hyperpigmentation.1

Because it’s an effective exfoliator, using glycolic acid regularly can help brighten the complexion. 
It’s this exfoliating property that also makes it an effective preventative against ingrown hairs. 
If you have large pores, glycolic acid can help make those appear smaller as well.

Many acne treatment products also contain glycolic acid. 
It isn’t an acne treatment per se, but glycolic acid can help keep pores clear from blockages, preventing comedones, blackheads, and inflamed breakouts from forming.

Although many sources claim glycolic acid gets rid of scars, this is one thing it simply can’t do. 
Glycolic acid can lighten dark discolorations left by acne or other wounds, and may soften the look of raised scars and pitted scars, but it will not make them disappear.3

For a more efficient treatment of scars, your best bet would be professional strength glycolic acid peels or a completely different scar treatment altogether.

Where You Can Find It
If you’re looking for glycolic acid, you have choices—and lots of them. This skincare darling can be found in a multitude of over-the-counter products.

Try your local drug store, department store, or skin spa and you’ll find plenty of cleansers, masks, toners, and moisturizers that contain this ingredient. 
Over-the-counter glycolic acid products typically come in strength of up to 10%.4

For stronger treatments, glycolic acid is also utilized in chemical peels available at the salon or your dermatologist’s office. 
Light duty glycolic acid peels up to 30% strength can be done by an esthetician at the salon or skin spa. Stronger peels of up to 70% can be had at the dermatology office.

Can you make a glycolic acid peel yourself? 
While glycolic acid is obtained from sugar cane (and also naturally found in some fruits) the sugar you buy at the store is not the same as glycolic acid.

Rubbing your face with sugar manually exfoliates the skin and will leave the skin feeling smoother. 
But it’s not going to give you the same results as glycolic acid treatment.

Skincare products contain other thoughtfully chosen ingredients to give a specific end result. 
You can definitely make your own skincare products, but they won’t give you results on par with a professional glycolic product or peel.

Choosing the Right Skin Treatment
The glycolic acid treatment you choose depends a lot on your skin type and what your end goals are. 
If you are simply wanting brighter, healthier-looking skin (or a reduction in breakouts and fine lines) an over-the-counter product is effective enough without stronger pro peels.

Using low concentrations of glycolic acid over long periods of time creates a cumulative effect; your skin will look better the longer you use it.

For treating specific skin issues like noticeable sun damage, dark spots or acne marks, and deeper lines and wrinkles, or for marked improvement of the skin quickly, a professional peel is a good option. But because peels deliver a higher percentage of glycolic acid than daily use products they will be more irritating and have a greater chance of side effects.5

When choosing any glycolic acid treatment, the percentage of glycolic acid is just one factor. 
The product’s pH is the other. A more acidic product will deliver a stronger and more effective treatment than a less acidic product, regardless of the percentage of glycolic acid.

So a product containing a low percentage of glycolic acid but with a lower (i.e. more acidic) pH will be more effective than a high percentage but low acidity product.

Unfortunately, the vast majority of skincare products simply list the percentage of glycolic acid used. 
They are not required to list the pH, so it can make it difficult to compare products apples-to-apples.

How to Use Glycolic Acid Safely
In general, glycolic acid is a very safe and effective skincare ingredient. 
To keep your skin safe, though, there are a few things to know before using glycolic acid.

First and foremost, you must wear sunscreen whenever you are using glycolic acid treatments.
Like all alpha-hydroxy acids, glycolic acid can make your skin more sensitive to the sun. 
You don’t want to undo all the good your glycolic acid is doing, and you definitely don’t want to end up with a nasty sunburn. 
Wear SPF of at least 30, please.

Allow your skin to acclimate to glycolic acid. 
If you are using an OTC product, start off by applying it just three times per week for a week or so. 
If your skin isn’t red or irritated, try using it four times a week for a week or two.

Continue slowly building up this way until you’re able to use it every day. 
If at any point your skin becomes irritated, scale back use for a period of time and try again.

For in-office or in-salon peels, you will probably start off with a lower concentration of glycolic acid. 
If your skin tolerates that reasonably well, you will most likely be bumped up to higher strengths for subsequent peels.

In the initial few days of treatment, your skin may feel a bit more rough than typical. 
This is normal and just means that the glycolic acid is working. 
Unless your skin is irritated, keep using your glycolic acid product. 
Smoother skin is just around the corner.

Don’t use glycolic acid, even OTC products, if you are currently using topical retinoids, like Retin-A (tretinoin) or Differin (adapalene), Accutane (isotretinoin), or any products that rapidly exfoliate the skin. 
Most importantly, if you’re under a dermatologist’s care make sure you get their OK before using any glycolic acid product or having a peel done.

A Word From Verywell
Glycolic acid OTC products and professional peels have been around a long time and have a safe and effective track record. 
Most skin types can use them without much trouble.

If you have very sensitive skin, you may want to stick with wash-off glycolic acid products like cleansers. 
These aren’t quite as irritating as leave-on glycolic acid treatments and allow your skin to build up a tolerance without (hopefully) too much irritation.

While glycolic acid is a wonderful skincare ingredient, if you’re looking for powerful anti-aging or anti-acne treatments, topical retinoids will give you more bang for your buck. 
They are prescription-only, though.

If you need any help choosing a glycolic acid product, your dermatologist can help you do so.

Glycolic acid is an example of an acne-fighting acid. 
This alpha hydroxy acid that’s derived from sugarcane can help those with frequent breakouts and a number of other skincare concerns.

Don’t go scavenging the aisles for glycolic acid just yet. 
There’s a lot to consider about glycolic acid, including how much to use and if it’s right for your skin

Benefits
When applied to the skin, glycolic acid works to break the bonds between the outer layer of skin cells, including dead skin cells, and the next skin cell layer. 
This creates a peeling effect that can make the skin appear smoother and more even.

For people with acne, the benefit of glycolic acid is that the peeling effects results in less “gunk” that clogs the pores. 
This includes dead skin cells and oil. With less to clog the pores, the skin clears and you usually have fewer breakouts.

Also, glycolic acid can affect the outer skin barrier, helping it retain moisture instead of drying your skin out. 
This is an advantage for acne-prone people because many other topical anti-acne agents, like salicylic acid and benzoyl peroxide, are drying.

ResearchTrusted Source has found that glycolic acid has antibacterial and antioxidant activity, which can also help improve your skin’s appearance when you have acne. 
Glycolic acid can also thicken skin by stimulating collagen growth.

How to use it
Glycolic acid is available in several forms, including over-the-counter and prescription treatments. 

These include:

face washes
lotions
peels
serums
skin care pads
Traditional wisdom is to start small, unless your dermatologist directs otherwise. 
You may wish to try a glycolic acid cleanser to see if your skin can tolerate glycolic acid.

A few things to remember. First, glycolic acid is an example of chemical exfoliation. 
While it’s not as fast as a scrub, the acid can penetrate more deeply and produce greater exfoliation over time. 
All this is to say — you likely won’t need to exfoliate with scrubs while also using glycolic acid. 
Your face may feel too sensitive otherwise.

Speaking of sensitive, you also don’t need to use multiple glycolic acid-containing products.
 Consistent use of one product with occasional spot treatments is often enough to keep your skin clear. 
Sometimes, your dermatologist may recommend a stronger, in-office peel, but this isn’t always the case.

Side effects
Glycolic acid isn’t for everyone. Some people have reactions to glycolic acid that can include symptoms such as swelling, itching, and burning sensations. 
Those with dry or sensitive skin types may find glycolic acid is too irritating for their skin.

In addition to these concerns, some people find they are more sensitive to sun when they use glycolic acid. 
Using a daily sunscreen can help reduce the sun exposure risks.

Cautions
If you have a darker skin tone, talk to your dermatologist about glycolic acids and its best uses for you. 
Most people can use glycolic acid effectively, but sometimes the acid can irritate darker skin tones and cause post-inflammatory hyperpigmentation or dark spots. 
Using lower concentrations and refraining from using too many glycolic acid-containing products can often reduce this risk.

The depth to which glycolic acid causes peeling often depends upon the concentration. 
For example, a 1 percent glycolic acid solution affects the pH level of three layers of skin, while a 10 percent solution can penetrate 10 to 20 layers, according to a 2018 journal articleTrusted Source.

This isn’t to say more is better (it’s not). Lower percentages can be less irritating and therefore more skin-friendly. 
You may find topical preparations that range from 1 percent up to 10 percent (usually reserved for spot treatments or a rinse-off peel only).

There are sources on the internet that sell higher percentages of glycolic acid, sometimes as much as 30 or 40 percent. 
These are medical grade peels, and you shouldn’t use them without a dermatologist oversight. 
A dermatologist knows how long the peel should stay on and if it’s right for your skin in the first place.

Products to consider
If your skin tolerates glycolic acid well, you can try a topical product. 

Here’s some examples:

Peel pads
These are usually used every other day, then sometimes every day if your skin isn’t too sensitive. 
One to try is the Bliss That’s Incredi-peel glycolic resurfacing pad.

Serum 
This 10 percent glycolic acid L’Oreal Paris Revitalift is marketed for improving skin tone, but also has acne-fighting potential.

Spot treatment
When you have a blemish (or blemishes), try Clean & Clear Advantage Acne Mark Treatment, which combines both glycolic and salicylic acid to treat pimples.

Toner
Applied nightly, The Ordinary Glycolic Acid 7% Toning Solution can provide mild exfoliation to reduce acne.

Glycolic acid vs. other acids
Glycolic acid isn’t the only acid in town. There are several other alpha hydroxy acids and natural acids skin care manufacturers use in their products. 
Here’s a look at them:

Hyaluronic acid
Hyaluronic acid is what doctors call a humectant. 
This acid attracts water to the outermost layers of skin to help them look and feel more hydrated. 
This acid isn’t an exfoliator like glycolic acid is, but is instead used to improve skin softness.

There are some issues with the pH of glycolic acid affecting how well the skin absorbs hyaluronic acid. 
If you’d like to use both of these acids, you may wish to use hyaluronic acid in the morning and glycolic acid at night.

If you put both on at the same time, your hyaluronic acid application isn’t likely to be effective.

Lactic acid
Lactic acid is a natural alpha hydroxy acid (AHA) made from acids that milk produces when it sours. 
This acid works similarly to glycolic acid because it promotes exfoliation by dissolving bonds with dead skin cells.

Lactic acid’s molecules aren’t as small as glycolic acid. 
Therefore, it may not penetrate the skin as well as glycolic acid.

However, lactic acid is typically less irritating to the skin than glycolic acid, according to an article in the journal MoleculesTrusted Source. 
If you have more sensitive skin, lactic acid may be the exfoliator of choice for you.

Salicylic acid
Salicylic acid is a beta hydroxy acid that cosmetic manufacturers harvest from tree bark.

The difference between beta and alpha hydroxy acids is oil and water. 
Alpha hydroxy acids are water soluble, so water can neutralize them if you experience burning or discomfort when applied. 
Beta hydroxy acids are oil-soluble. 
As a result, they can penetrate into an oil-filled pore to reduce buildup.

Salicylic acid is especially effective on very oily skin and when you have blackheads in addition to acne pimples. 
Both glycolic and salicylic acid can be effective acne fighters.

The final word on acids
While there are lots of acids and active ingredients (such as retinol) available to improve skin cell turnover, it’s important not to use them to excess because they dry out the skin.

Salicylic acid and glycolic acid can pair well together as spot treatments. 
But retinol and glycolic acid may be too drying for most people.

Other uses of glycolic acid
In addition to acne, dermatologists use glycolic acid to treat the following skin conditions:

age spots
hyperpigmentation
melasma
scars
skin roughness
These different potential uses make glycolic acid a versatile ingredient for those seeking to improve their skin’s appearance.

When to see a dermatologist
If you have acne, especially more severe forms like cystic acne, it’s a good idea to check with your dermatologist first before using glycolic acid.

This is especially true if your doctor already has you using prescription products, including antibiotics. 
It’s possible the combination of glycolic acid and other products could do more harm than good by making your skin produce too much oil, further clogging your pores.

You should also see your dermatologist if you are considering a glycolic acid peel. 
These are higher concentrations of glycolic acid that may offer greater results in terms of exfoliation, but require a knowledgeable professional.

According to a 2013 review of multiple studies, glycolic acid peels of between 30 and 70 percent can improve the appearance of acne and acne scarring.

Some skin types and even skin shades may be in appropriate for glycolic acid peels due to risks for irritation and hyperpigmentation.

The bottom line
Glycolic acid is a multitasking skincare ingredient that can help you fight acne and improve your skin’s appearance. 
Due to concerns for irritation, it’s best to talk to your dermatologist before you start using it.

Starting with lower percentage formulations can help your skin adjust and reduce irritation risks over time.

1209322 [Beilstein]
201-180-5 [EINECS]
2-Hydroxyethanoic acid
79-14-1 [RN]
Acetic acid, 2-hydroxy- [ACD/Index Name]
Acide glycol [French] [ACD/IUPAC Name]
Acide hydroxyacétique [French]
a-Hydroxyacetic acid
Glycol acid [ACD/IUPAC Name]
Glycolic acid [Wiki]
Glycolsäure [German]
Hydroxyessigsäure [German] [ACD/IUPAC Name]
Kyselina glykolova [Czech]
Kyselina hydroxyoctova [Czech]
QV1Q [WLN]
1,2-Ethanediol [ACD/Index Name]
102962-28-7 [RN]
1-hydroxy-ethanoic acid
26009-03-0 [RN]
2-oxonioacetate
4-03-00-00571 (Beilstein Handbook Reference) [Beilstein]
Acetate ion
Acetic acid [ACD/Index Name] [ACD/IUPAC Name] [Wiki]
D(-)-TARTARIC ACID
D-malate
EDO
GLV
Glycocide
Glycolic acid 100 µg/mL in Acetonitrile
Glycolic acid, 66-70% aqueous solution
glycolic acid, crystal, reagent
Glycolic acid, pure, 99.5%
Glycollic acid
Glyoxylic acid [Wiki]
GOA
HOCH2COOH
http://www.hmdb.ca/metabolites/HMDB0000115
https://www.ebi.ac.uk/chebi/searchId.do?chebiId=CHEBI:17497
Hydroxy-acetic acid
Hydroxyethanoic acid
Kyselina glykolova
MFCD00868116 [MDL number]
MLT
STR00936
TAR
WLN: QV1Q
α-Hydroxyacetic acid
α-Hydroxyacetic acid
乙醇酸 [Chinese]

As far as peeling agents go, Glycolic acid is one of those miracle ingredients for brighter, more radiant complexion. 
The potent ingredient (that derms swear by, btw) is found in a slew of cult skincare products, purported to re-texturize dull, uneven, and even acne-prone skin and reverse signs of aging. You’ve likely heard about Glycolic acid and its benefits, and maybe you’ve even already hopped on the bandwagon and experimented with the creme de la creme of the Alpha Hydroxy Acid family. 
These are a lot of claims for one ingredient to live up to, so I asked Dr. Carmen Castilla of Tribeca Skin Center, which offers an array of peels, including Glycolic, Salicylic, PCA, and other peels in their lineup, why Glycolic should nab a spot in your beauty arsenal.

What is Glycolic acid?
It’s the answer to all your hyper-pigmentation woes, that’s for sure. 
“Glycolic acid is an AHA, or Alpha Hydroxy Acid. 
It’s a water soluble acid and an ingredient that increases luminosity of the skin because it exfoliates the outermost dead layer of the skin, which is called the Stratum Corneum, and improves the reflection of light on the skin. 
Sometimes people use scrubs, which are abrasive and can cause irritation, but unlike scrubs, when Glycolic acid is used at the right percentage and when done appropriately, it’s a much gentler way to exfoliate the skin.”

What types of skin does it treat?
Basically, if you’re a human being you can probably benefit from Glycolic acid. 
The ingredient specifically treats wrinkles, hyper-pigmentation, and acne prone skin, so if one or more of these is a skincare concern of yours, it’s worthy of your top shelf.
 It takes that very top layer of the skin and removes it. 
As we age, our skin exfoliates slower so exfoliating the skin with a little help from Glycolic reveals newer skin, which becomes more even and radiant.

“Glycolic acid helps to separate the connections between keratinocytes [skin cells] in the outer layers of skin without rough, mechanical exfoliation techniques and promotes exfoliation,” Dr. Krant says. “In this way, it can artificially speed up cell turnover and bring fresher, younger cells to the surface.”

Abstract
Chemical peels have been time-tested and are here to stay. 
Alpha-hydroxy peels are highly popular in the dermatologist’s arsenal of procedures. 
Glycolic acid peel is the most common alpha-hydroxy acid peel, also known as fruit peel. 
It is simple, inexpensive, and has no downtime. This review talks about various studies of glycolic acid peels for various indications, such as acne, acne scars, melasma, postinflammatory hyperpigmentation, photoaging, and seborrhea. 
Combination therapies and treatment procedure are also discussed. 
Careful review of medical history, examination of the skin, and pre-peel priming of skin are important before every peel. 
Proper patient selection, peel timing, and neutralization on-time will ensure good results, with no side effects. 
Depth of the glycolic acid peel depends on the concentration of the acid used, the number of coats applied, and the time for which it is applied. 
Hence, it can be used as a very superficial peel, or even a medium depth peel. 
It has been found to be very safe with Fitzpatrick skin types I–IV. 
All in all, it is a peel that is here to stay.

Keywords: acne scar, melasma, photoaging, chemical peel, alpha-hydroxy peel
Go to:
Introduction
Alpha-hydroxy peels have been popular in dermatological practice for years and are well-established. 
They have practically no downtime, and are usually superficial or medium depth peels. 
They have therapeutic as well as cosmetic benefits when used on skin. 
Glycolic acid (GA) obtained from sugarcane is used in the most common alpha-hydroxy acid peel.

GA has the smallest molecular weight amongst all the alpha-hydroxy acids. 
It penetrates skin easily, making it a popular peel agent.
GA has two carbon atoms: one carbon atom is with a carboxyl group and the other carbon atom is with a hydroxyl group. 
GA is extremely hydrophilic. The pH of a non-buffered solution ranges from 0.08–2.75.4 
Previous authors have recommended the use of a buffered or partially neutralized GA, which is safer than free GA.
Glycolic acid peels are commercially available as free acids, partially neutralized (higher pH), buffered, or esterified solutions.
They are available in various concentrations ranging from 20%–70%. 
The higher the concentration and lower the pH, the more intense the peeling will be.
In general, gel formulations have a slower penetration time and are easier to control

Fabbrocini, in 2009, classified glycolic peels as: very superficial (30%–50% GA, applied for 1–2 minutes); superficial (50%–70% GA, applied for 2–5 minutes); and medium depth (70% GA, applied for 3–15 minutes).8 GA peels have antiinflammatory, keratolytic, and antioxidant effects. 
GA targets the corneosome by enhancing breakdown and decreasing cohesiveness, causing desquamation.
The intensity of GA peel is determined by the concentration of the acid.
A peels need to be properly neutralized in order to stop acidification of the skin.

Go to:
Material and methods
Application methods
Before starting a series of GA peels, the status of the skin should be assessed for the occurrence of any dry or scaly patches on skin, open sores that may have become acidified through the use of GA/tretinoin creams.
Priming the skin with hydroquinone, or topical retinoids, before performing a peel has been found to increase peel efficacy and reduce the risk of postinflammatory hyperpigmentation.
After the skin has been cleansed and degreased, GA solution is applied using cotton buds or a brush in a sequential manner starting from the forehead to the left cheek, chin, right cheek to cover the entire face. Care is taken to protect the eyes and the corners of the nose and lips. 
The peel is neutralized within 3–5 minutes, or when uniform erythema is seen. 
If frosting is observed in any particular area before the set time or end-point, it is important to neutralize the peel immediately. 
It is always better to start with a low concentration (20% GA) and increase the concentration and application time during subsequent sessions.
Peeling is repeated once every 15 days for 4–6 months until the desired result is achieved.

Mechanism of action
Glycolic acid peels have antiinflammatory, keratolytic, and antioxidant effects. 
GA targets the corneosome by enhancing breakdown and decreasing cohesiveness, causing desquamation.
The intensity of peel is determined by the concentration of the acid, the vehicle used to carry it, the amount of acid applied, and the technique used.10

GA peels need to be properly neutralized to stop acidification of the skin. 
Applying acid to the skin saturates the ability of cells to resist acidification; excess acid must be neutralized to avoid burning. 
Alpha-hydroxy acid peels can be neutralized with water or with basic solutions, such as ammonium salts, sodium bicarbonate, or sodium hydroxide.

Indications
Acne, acne scars, melasma, postinflammatory hyperpigmentation, photoaging, and seborrhea are indications for chemical peeling.
GA may be used in acne also to normalize keratinization and increase epidermal and dermal hyaluronic acid and collagen gene expression.

Acne and acne scars
In a study by Wang et al, Asian patients with skin type IV with acne were treated with 35% GA and 50% GA peels, once in 3 weeks for 10 weeks. 
There was significant resolution of comedones, papules, and pustules. 
The skin texture improved and follicular pore size reduced. 
Most of the patients were found to have brighter and lighter looking skin. 
Consistent and repetitive treatment with GA was needed for the apparent improvement of acne scars and cystic lesions. 
Only a small percentage of patients (5.6%) developed side effects, in the form of postinflammatory hyperpigmentation, mild skin irritation, and exacerbation of herpes simplex infection. Hence, GA peels were found to be ideal as an adjunctive treatment for acne.21

In another study by Atzori et al, 70% GA was used in comedonic acne, papulopustular, and nodular/cystic acne. 
While comedones improved rapidly, papulopustular acne improved after six peel sessions, and nodulocystic lesions required ten sessions at three-week intervals. 
A significant improvement of coexisting post-acne superficial scarring was noted. Patient tolerance and compliance were both found to be excellent.22

Kim et al did a comparative study using 70% GA and Jessner’s Solution (resorcinol 14%, lactic acid 14%, and salicylic acid 14%, in an alcohol base), respectively, in two groups of patients with acne. 
Three peel sessions were done for each group. 
Though acne improved in both to the same extent, there was more exfoliation seen in the Jessner’s Solution group. Hence, GA was found to be the better tolerated of the two peels for the treatment of acne in Asian patients.23

Grover and Reddu conducted a study of 41 patients with Fitzpatrick Skin Type III–V, of whom 16 patients had acne. 
Initially, they used 10% GA for a period of 1–2 minutes, then gradually increased the duration to 5 minutes and concentration to 30% GA. 
All patients had greasy skin with high sebaceous activity. 
The severity of acne was graded on a four-point scale, which revealed that mild to moderate acne was seen in eight patients, severe acne in seven patients and one patient had nodulocystic acne. Apart from comedones, papules, and pustules, a significant number of patients had scarring and pigmentation. 
After undergoing peels with GA, the therapeutic response was good in 75% of patients, on the basis of both patient and observer assessments. 
Patients with postinflammatory hyperpigmentation and scarring showed excellent improvement. 
Significant decrease in the number of comedones and papulopustules was observed in patients with mild to moderate acne. 
However, the patient with nodulocystic acne lesions did not respond well to therapy. 
Compared to the 90% response seen by Wang et al,21 75%–78% of patients with acne, excepting the patient with nodulocystic acne, showed a good-to-fair response with GA peels.24

Kessler et al compared 30% GA versus 30% salicylic acid (SA) peels in 20 patients with mild to moderate acne, using a split-face design. 
Peels were performed every 2 weeks for a total of six treatments. Both peels improved acne. 
However, the authors found that the SA peel had better sustained efficacy (ie, number of acne lesions, and improvement rating by blinded evaluator) and fewer side effects than GA, presumably due to the greater lipophilicity of SA. 
The authors agreed with the impression that SA peels are better tolerated than GA peels in acne patients.

A study by Erbağci and Akçali concluded that a 70% GA peel performed every 2 weeks resulted in significant improvement in atrophic acne scarring, as compared to 15% GA cream used daily.
In one group of 23 patients, GA peels were performed bi-weekly with increasing application time and acid concentration from 20%–70%. 
A second group of 20 patients was instructed to use 15% GA cream twice daily for a period of 24 weeks. 
It was seen that six patients, using 70% GA, showed significantly better results than daily use of 15% GA for 24 weeks (P < 0.05). 
Furthermore, apparently good responses were observed in the peel group only (P < 0.01).26

In the author’s experience, GA peels are excellent for use on Indian skin. 
Patients with Fitzpatrick’s skin types III–IV with post acne pigmentation are treated with 20% GA peel for the first three sessions. 
The concentration of GA is then increased to 35% in the subsequent five to six sessions. 
There is an interval of 15 days between sessions. Patients respond well, with clearance of lesions, in around eight to ten sessions, without any adverse effects

Melasma
Lin and Tham studied the use of GA peels in ten Asian women. Concentrations of 20%–70% GA were administered every 3 weeks, either alone or in combination with a topical regimen of 2% hydroquinone plus 10% GA. 
There was significant improvement (P < 0.06) in melasma and fine facial wrinkling in patients who received the combination of creams and peeling.27

Kalla et al did a comparative study of 55%–75% GA versus 10%–15% trichloroacetic acid (TCA) peels in 100 patients with recalcitrant melasma. 
The peels were conducted at 15-day intervals in both groups. It was seen that the response to TCA was rapid, and produced better results than GA. 
However, relapse was more common in the TCA group (25%) than in the GA group (5.9%).28

In a study by Javaheri et al, peeling was performed upon 15 Indian females with melasma, using 50% GA, once-monthly for 3 months. 
An improvement in Melasma Area Severity Index (MASI) score was observed in 91% of patients (P < 0.01). 
A better response was seen in patients with epidermal melasma, compared to those with mixed melasma (P < 0.05).29

In a study by Sarkar et al, 20 Indian patients received serial GA peels (30% GA for the first three sittings; 40% GA for the next three sittings), combined with the modified Kligman’s formula (2% hydroquinone, 0.025% tretinoin, and 1% mometasone). 
A further 20 Indian patients received only the modified Kligman’s formula, with no peeling. 
In both groups, a significant decrease in the MASI score was observed from baseline to 21 weeks (P < 0.001). 
However, the GA peel group showed more rapid and greater improvement (P < 0.001).30

A comparative study by Hurley et al was done on 21 Hispanic women with bilateral, epidermal, and mixed melasma to assess the efficacy of 4% hydroquinone cream versus 4% hydroquinone cream combined with GA peels. Patients received GA peels (20%–30% GA) every 2 weeks to one side of the face only, in addition to twice-daily application of 4% hydroquinone cream to the other side of the face. 
Pigmentation was measured objectively using a Mexameter® (Courage + Khazaka electronic GmbH, Cologne, Germany) and the MASI, and measured subjectively using a linear analog scale and physician and patient global evaluation. Both sides of the face showed a reduction of pigmentation, and there was no significant difference.31

The concentration of GA used by Hurley et al was low (20%–30%), compared to the 30%–40% GA used by Sarkar et al.
This could be a reason for the difference in the results they observed.

In a study by Khunger et al, patients with melasma were treated with a 70% GA peel on one half of the face, while the other half was treated with a 1% tretinoin peel. 
A significant decrease in the modified MASI score was observed on both facial sides from baseline to 6 weeks, and then from 6 to 12 weeks (P < 0.001).33 A study by Kligman found the two peels to be equally effective and well tolerated.34

In 15 cases of melasma (epidermal: 80%; dermal: 13.3%; and mixed: 6.6%), 52.5% GA concentration was applied for 3 minutes. 
There was good to fair response in patients with epidermal and mixed melasma, while no significant improvement was seen in dermal melasma.24

Serial GA peels (from 35%–50%, and 70% every second peel) plus combination topical therapy (azelaic acid and adapalene) in 28 women with melasma found better results in the group receiving chemical peel plus topical therapy (P = 0.048), but only when the GA concentration was 50% or higher.35

In another study, a triple combination cream consisting of fluocinolone acetonide 0.01%, hydroquinone 4%, and tretinoin 0.05% was used in an alternating sequential treatment pattern, cycling with a series of GA peels, for the treatment of moderate to severe melasma. 
Spectrometry measurement of the difference in melanin between involved and uninvolved skin confirmed that hyperpigmentation was significantly reduced at 6 and 12 weeks, compared with baseline (P < 0.001), with evaluations showing improvement of 90% or more by week 12.36

In another study, 10 patients with melasma were treated with a triple combination of tretinoin 0.05%, hydroquinone 4%, and mometasone furoate 0.1%. 
Serial GA peels were performed at three-weekly intervals, with application times from 2–6 minutes, depending on tolerance and erythema. 
Glycolic acid of 57% concentration, with 55% free acid, and pH 2.3 was used on the face in gradually increasing durations of application. 
Significant reduction in melasma was noted after four peels. 
One patient developed irritation and hyperpigmentation, while one developed persistent erythema. 
No other side effects were reported.

In a comparative study of 10%–20% TCA versus 20%–35% GA peels for the treatment of melasma, similar improvement was seen with both peels. 
However, the GA peel was seen to be associated with fewer side effects than the TCA peel, and gave the added benefit of facial rejuvenation.

In another similar study of 15% TCA peel versus 35% GA peel for the treatment of melasma, there was no statistically significant difference in efficacy. 
Both peels significantly reduced MASI scores, and both were found to be equally effective in the treatment of melasma. 
It was also seen that adverse effects were more common with TCA than with GA peels.

Postinflammatory hyperpigmentation
In a pilot study by Burns et al, postinflammatory hyperpigmentation was treated with a series of GA peels in skin types IV–VI. 
No adverse effects were reported in dark skin, and the GA peel proved to be efficacious
This echoed the study by Grover and Reddu, in which skin types III–V showed overall improvement of skin texture in almost all patients.24

In the author’s experience with cases of postinflammatory hyperpigmentation in skin types III and IV, a series of 35% GA peels has produced good results. 
All patients are instructed to use sunscreen before and after the peel. 
Priming is done with a combination of mometasone and tretinoin 0.025% creams for 3 weeks before the peel. 
The patient is asked to stop the creams 1 week before the peel. 
Post-peel care, in the form of sun protection, and avoidance of facial scrubs, steam, and sauna is advised. 
Complete resolution of postinflammatory hyperpigmentation is commonly seen after six to eight peel treatments 

Photodamage
Photodamage, in the form of dyschromias, actinic keratoses, solar lentigines, and fine wrinkling has also shown improvement with a combination of GA and TCA peels.
In a study of 50% GA peels by Newman et al, there was improvement in mild photoaging of skin. Other significant improvements were noted, including decreases in rough texture and fine wrinkling, fewer solar keratoses, and slight lightening of solar lentigines. 
Histologic analysis showed thinning of the stratum corneum, granular layer enhancement, and epidermal thickening. 
Some specimens showed an increase in collagen thickness in the dermis.
Glycolic acid peels do not affect deep wrinkles or deep pigmentations.3

Combination treatments
GA peels have frequently been combined with other peels and treatments, to give better results. 
In a study by the author, microneedling was combined with 35% GA peel to treat acne scars in patients with skin type III–IV. 
Microneedling was performed six-weekly, and 35% GA peel was performed 3 weeks after each microneedling session. 
There was significant improvement in superficial and moderately deep atrophic box scars and rolling scars. 
In addition, there was improvement in skin texture and reduction in post-acne pigmentation.46

GA and TCA peels are performed sequentially in cases of postinflammatory hyperpigmentation, post-acne pigmentation, and melasma. 
This combination has been found to produce a deeper and more uniform peel than TCA used alone.

Combining Jessner’s Solution and GA for the treatment of photoaged skin, actinic keratoses, and rhytides resulted in a uniform GA peel, but the risk of overpeel and scarring are high, especially in dark-skinned individuals.
GA has been combined with 5-fluorouracil to treat actinic keratosis. 
Pretreatment of the skin with 5-fluorouracil 5% increases the efficacy of the treatment and shortens the healing time.

GA peeling has also been used in combination with microdermabrasion, for the treatment of acne vulgaris and superficial acne scars, in order to increase treatment efficacy and achieve treatment goals within a shorter time. 
Alpha-hydroxy acid peels decrease corneocyte cohesion, making the abrasion more efficient.
However, combining GA peels with microdermabrasion at the same session could lead to postinflammatory hyperpigmentation in skin types III–VI. 
Therefore, care should be taken with darker skin types.52 Briden et al reported good patient satisfaction when using superficial GA peels with microdermabrasion for photoaging.53

In a study on photodamaged skin, an intense light that combined a narrow-band (405–420 nm) blue light (antiinflammatory) emission with a near-infrared (850–890 nm) emission was applied to the skin. Concomitant glycolic peels were performed, and daily Vitamin C cream was given. 
Results showed significant improvements in pore size, rhytids, and radiance.
GA peeling is also combined with Vitamin C in cases of melasma and postinflammatory hyperpigmentation. 
In a patient with melasma, 70% GA peeling was performed on one side of the face, along with iontophoresis with nanosome vitamin C; 70% GA peeling alone was performed on the other side of the face. 
It was seen that both sides improved, but that the side treated with iontophoresis and nanosome Vitamin C showed better results.
Superficial GA peels can also be used with botulinum toxin and fillers in order to obtain overall improvement in wrinkles, skin tone, texture, radiance, and clarity. 
In one study, the interval between peels and fillers was 1 week. The peel was administered after injecting botulinum toxin during the same visit, or the procedures were separated by one or more days to minimize the potential for side effects.

Side effects
The GA peel is time-tested. Proper selection of patients, timing of peel, and neutralization on-time should ensure good results and no side effects. 
Superficial peels using alpha-hydroxy acids increase the epidermal activity of enzymes, leading to epidermolysis and exfoliation.

The minor side effects reported are: erythema, stinging sensation, sensation of pulling of facial skin, mild burning, and transient postinflammatory hyperpigmentation. 
Unbuffered GA can cause erosive blisters and scarring.
In rare cases, hypopigmentation, persistent erythema, and flare-up of pimples have been reported.

Epidermolysis may occur if the patient has used topical retinoids, anti-acne creams, or skin lighteners in days prior to the peel.
Other causes are excessive facial scrubbing before the peel, and pre-existing dry skin. It is important to stop priming agents around 1 week before the peel. 
Sun exposure after the peel may cause postinflammatory hyperpigmentation.60 There has been one report of contact urticaria with a GA peel.

Go to:
Discussion
Glycolic acid is the alpha-hydroxy acid used most commonly by dermatologists for chemical peeling. 
It is used in concentrations from 20%–70% in all skin types. 
It should be used in lower concentrations initially, and then the strength of the peel should be gradually increased in subsequent sessions. 
There should be a minimum interval of 2 weeks between two treatment sessions. Peel neutralization is extremely important and it depends on erythema seen. 
However, in dark skin, it may be difficult to appreciate erythema. 
In such cases, it is better to time the peel between 3–5 minutes and judge the desired end-point depending on the time.
The longer the duration, the deeper the depth of the peel. Pre-peel priming and post-peel care are equally important. 
Depending on the condition, tretinoin, kojic acid, and hydroquinone can be used for pre-peel priming. 
In order to avoid postinflammatory hyperpigmentation and scarring in dark-skinned patients, it is important to avoid facial scrubs, depilatory creams, waxing, bleaching, microdermabrasion, and laser hair removal for at least 1 week before the procedure. 
After the peel, the patient should be advised to avoid sun exposure, facial scrubs, loofahs, picking at the peeling skin, taking steam inhalation, and using creams that cause exfoliation. 
The patient must be instructed to use a broad spectrum sunscreen during the day, and a moisturizer at night. 
The GA peel is safe for a correctly selected patient when the correct technique is used. 
It does not produce any systemic toxicity.
It can be combined with other treatment modalities for better cosmetic outcomes.

Go to:
Conclusion
The GA peel has proven to be efficacious through the years. 
Combining the GA peel with other treatment modalities may become more common in future. 
However, the GA peel is here to stay, as it is a simple, evidence-based, result-oriented, and cost-effective procedure.

Acetic acid, 2-hydroxy-
Acetic acid, hydroxy-
Glycolic acid
glycolic acid
Glycollic acid

EC Inventory
Glycollic acid
glycollic acid
Hydroxyacetic acid
Hydroxyethanoic acid
Kyselina glykolova
Kyselina hydroxyoctova

Translated names
Acid glicolic (ro)
Acide glycolique (fr)
Acido glicolico (it)
Aċidu glikolliku (mt)
Glikolio rūgštis (lt)
Glikolna kiselina (hr)
Glikolna kislina (sl)
Glikolsav (hu)
Glikolskābe (lv)
Glycolic acid (no)
glycolsyre (da)
Glycolzuur (nl)
Glykolihappo (fi)
glykolová kyselina/2-hydroxyethanová kyselina (cs)
Glykolsyra (sv)
Glykolsäure (de)
Glükoolhape (et)
Kwas glikolowy (pl)
kyselina glykolová (sk)
Ácido glicólico (es)
Ácido glicólico (pt)
Γλυκολικό οξύ (el)
Гликолова киселина (bg)

CAS names
Acetic acid, 2-hydroxy-
IUPAC names
2-hydroxy acetic acid

2-Hydroxyacetic acid
2-hydroxyacetic acid
2-Hydroxyethanoic acid
2-hydroxyethanoic acid
glycol acid
GLYCOLIC ACID
Glycolic Acid
Glycolic acid
Glycolic Acid
Glycolic acid
glycolic acid
GLYCOLLIC ACID
Glycollic acid
glycollic acid
Glycollic acid
glycollic acid
Glykolsäure
Glykolsäure … %
Hydroxyacetic Acid

Trade names
Glycolic acid
Glycos Basic 57
Glycos Basic 70
Glycos Clear 70
Glypure 70
Glytech Basic 57
Glytech Basic 70

Other identifiers
1033720-45-4

CAS number
1033720-45-4

Deleted CAS number
1033720-48-7

CAS number
1033720-48-7

Deleted CAS number
259744-22-4

CAS number
259744-22-4

Deleted CAS number
702627-33-6

CAS number
702627-33-6

Deleted CAS number
79-14-1

glycolic acid
hydroxyacetic acid
2-Hydroxyacetic acid
79-14-1
Glycollic acid
Hydroxyethanoic acid
Acetic acid, hydroxy-
Acetic acid, 2-hydroxy-
Caswell No. 470
alpha-Hydroxyacetic acid
Kyselina glykolova
Kyselina glykolova [Czech]
Kyselina hydroxyoctova
HOCH2COOH
2-Hydroxyethanoic acid
Kyselina hydroxyoctova [Czech]
Glycocide
EPA Pesticide Chemical Code 000101
GlyPure
HSDB 5227
NSC 166
AI3-15362
UNII-0WT12SX38S
MFCD00004312
GlyPure 70
BRN 1209322
GLYCOLLATE
Acetic acid, hydroxy-, homopolymer
.alpha.-Hydroxyacetic acid
Acetic acid, 2-hydroxy-, homopolymer
0WT12SX38S
NSC166
CHEBI:17497
NSC-166
Glycolic acid, 70%
Glycolic acid, 99%
Glycolic acid-13C2
Polyglycollic acid
26124-68-5
GOA
glycolicacid
Dexon (polyester)
C2H4O3
Poly(L-glycolic acid)
Glypure 70 homopolymer
POLYGLYCOLIC ACID
Glycolic acid homopolymer
EINECS 201-180-5
Hydroxyacetic acid homopolymer
Hydroxyethanoate
a-Hydroxyacetate
CCRIS 9474
hydroxy-acetic acid
alpha-Hydroxyacetate
a-Hydroxyacetic acid
Glycolic Acid 70%
26009-03-0
2-hydroxy acetic acid
2-hydroxy-acetic acid
ACMC-209pgf
omega-Hydroxy fatty acid
2-hydroxyl ethanoic acid
Glycolic acid, polyesters
HO-CH2-COOH
DSSTox_CID_5363
bmse000245
WLN: QV1Q
EC 201-180-5
DSSTox_RID_77763
Glycolic acid (7CI,8CI)
DSSTox_GSID_25363
4-03-00-00571 (Beilstein Handbook Reference)
KSC377Q2F
ARONIS23902
Glycolic acid, p.a., 98%
[O]C(=O)CO
[O]CC(O)=O
Acetic acid, hydroxy- (9CI)
CHEMBL252557
DTXSID0025363
CTK2H7822
Glycolic Acid, Crystal, Reagent
C(=O)(O)[C]O
Glycolic acid solution, 56-58%
BCP28762
Glycolic acid, >=97.0% (T)
KS-000000CK
STR00936
ZINC4658557
Tox21_301298
ANW-37261
BBL020025
s6272
STL197955
AKOS000118921
Glycolic acid, ReagentPlus(R), 99%
CS-W016683
DB03085
Glycolic acid solution, puriss., 70%
HY-W015967
MCULE-9792551388
CAS-79-14-1
NCGC00160612-01
NCGC00160612-02
NCGC00257533-01
AK128829
Glycolic acid, 66-70% aqueous solution
K398
SC-26092
SC-85771
Glycolic acid solution, CP, 70% in H2O
FT-0612572
FT-0669047
G0110
G0196
Glycolic acid 100 microg/mL in Acetonitrile
Glycolic acid, SAJ special grade, >=98.0%
C00160
C03547
Glycolic acid, Vetec(TM) reagent grade, 98%
HYDROXYACETIC ACID; HYDROXYETHANOIC ACID
M-7418
11046-EP2269610A2
11046-EP2269988A2
11046-EP2270002A1
11046-EP2270003A1
11046-EP2270008A1
11046-EP2270011A1
11046-EP2275401A1
11046-EP2275413A1
11046-EP2277848A1
11046-EP2277867A2
11046-EP2280003A2
11046-EP2281563A1
11046-EP2284160A1
11046-EP2284178A2
11046-EP2284179A2
11046-EP2287156A1
11046-EP2289510A1
11046-EP2289879A1
11046-EP2289890A1
11046-EP2292617A1
11046-EP2295424A1
11046-EP2298735A1
11046-EP2298755A1
11046-EP2301931A1
11046-EP2301937A1
11046-EP2301940A1
11046-EP2305257A1
11046-EP2305646A1
11046-EP2305651A1
11046-EP2308851A1
11046-EP2308854A1
11046-EP2311807A1
11046-EP2311842A2
11046-EP2314588A1
11046-EP2314593A1
11046-EP2316457A1
11046-EP2316458A1
11046-EP2316459A1
11046-EP2316825A1
11046-EP2316826A1
11046-EP2316827A1
11046-EP2316828A1
11046-EP2372017A1
11046-EP2374786A1
11046-EP2374787A1
11046-EP2374895A1
11046-EP2380871A1
47926-EP2301544A1
47926-EP2308851A1
47926-EP2311810A1
49125-EP2272848A1
49125-EP2281824A1
49125-EP2292613A1
49125-EP2295408A1
49125-EP2295426A1
49125-EP2295427A1
49125-EP2295430A2
49125-EP2295431A2
49125-EP2305254A1
49125-EP2305679A1
49125-EP2311823A1
Glycolic acid, BioXtra, >=98.0% (titration)
Glycolic acid solution, technical, ~55% in H2O
Q409373
J-509661
F2191-0224
Glycolic acid solution, high purity, 70 wt. % in H2O
Hydroxyacetic acid; Hydroxyethanoic acid; Glycollic acid
Z1259155884
287EB351-FF9F-4A67-B4B9-D626406C9B13
Glycolic acid solution, technical grade, 70 wt. % in H2O
Glycolic acid, certified reference material, TraceCERT(R)
Glycolic acid, anhydrous, free-flowing, Redi-Dri(TM), ReagentPlus(R), 99%
Glycolic Acid, Pharmaceutical Secondary Standard; Certified Reference Material
O7Z

The Benefits of Glycolic Acid
You’ll find Glycolic Acid in many chemical peels due to high percentages being very effective for skin treatments (if done safely and properly!). I
ts even safe enough to use on sensitive skins.
Glycolic Acid can be used in our daily skincare products, without causing any irritation. 
This is particularly popular with Glycolic Acid for the face, facial washes and cleansers, bringing along rejuvenating benefits from your first step of your cleansing routine
Derived from plants – such as sugar cane, pineapple and sugar beets- its botanical properties help to treat skin conditions such as Psoriasis, Melasma and Seborrheic keratosis
Glycolic Acid is the holy grail for exfoliation, effectively removing the outermost layer of dead cells from the complexion, revealing brighter, fresher skin.
Products that contain Glycolic Acid are used often to treat scarring, skin discoloration and signs of aging, like fine lines and wrinkles. 
If you suffer from dull, pigmented or aging skin, look to invest in a once a week exfoliating treatment or an at-home peel product infused with Glycolic Acid.
It can transfer water molecules from the air into the skin tissue, replenishing any lost moisture. 
This makes it an effective ingredient in moisturizers when used at low strengths.
Studies show that Glycolic Acid skincare assists with boosting collagen production, which is brilliant for plumping up the skin. 
Collagen is a vital structural protein, helping the skin tissue remain firm and resist wrinkling. 
At low strengths, glycolic acid is the key ingredient to look out for when it comes to shopping anti-aging moisturizers or face masks, ideal for plumping, smoothing and refreshing your complexion

How Does It Work?
It reacts with the top layer of skin, breaking it down by dissolving sebum and other substances that bind cells together
Made up of small molecules, it is able to penetrate the skin deeply and easily. 
This makes it most effective for treating fine lines, acne, blackheads, dullness, oiliness and uneven texture.
Dead skin cells are sloughed off revealing smoother, brighter, younger looking skin.
The products available which feature Glycolic Acid range in percentage of concentration, and also pH levels such as SkinMedica. 
A product with pure Glycolic Acid in a lower concentration is much more effective than one which includes it along with other ingredients. 
However, for daily use, you may want a moisturizer which fuses Glycolic Acid with natural ingredients.

Who Can Use It?
Glycolic is an acid the encourages exfoliation, which means irritation can sometimes occur.  
Although Glycolic acid comes with great skin boosting benefits, it is good for almost any skin type.  
Generally people with very sensitive skin types will want to avoid using Glycolic acid as they may find it too irritating.

How Often Should I use it?
This really depends on skin type, age, and level of sensitivity of skin.  
Different products can be used in different frequencies.  
Generally people want to reduce the amount of Glycolic acid based products used when skin begins to feel sensitive.

What does Glycolic Acid do?
When applied to the skin, the potent little ingredient reacts with the top layer to break down sebum and exfoliate away the outer dead layer. 
Once the Glycolic Acid has swept that junk away, skin can reflect light better to reveal smoother, brighter-looking skin

Glycolic acid (or hydroxyacetic acid) is the smallest α-hydroxy acid (AHA). 
It appears in the form of a colorless, odorless and hygroscopic crystalline solid that is highly soluble in water and related solvents. 
Glycolic acid is associated with sugar-crops and is isolated from sugarcane, sugar beets, pineapple, canteloupe, and unripe grapes.

Due to its excellent capability to penetrate skin, glycolic acid finds applications in skin care products, most often as a chemical peel performed by a dermatologist in concentrations of 20%-80% or at-home kits in lower concentrations of 10%. 
It is used to improve the skin’s appearance and texture. 
It may reduce wrinkles, acne scarring, hyperpigmentation and improve many other skin conditions. 
Once applied, glycolic acid reacts with the upper layer of the epidermis, weakening the binding properties of the lipids that hold the dead skin cells together. This allows the outer skin to “dissolve” revealing the underlying skin.

Glycolic Acid Benefits



Glycolic acid moves beyond its primary function as an exfoliant and provides a number of other benefits as a result of this key capability. 



Glycolic acid is part of the family of alpha hydroxy acids (AHA) which are all made from natural sources such as fruit, milk, or sugar and in this case, it’s the latter. 
Generally speaking, the benefits of AHAs on the skin include exfoliation, brightening, smoothing, anti-aging, and acne prevention, and glycolic acid is no exception. 
But what makes glycolic acid standout from the pack is its chemical structure. 
Because the molecules of glycolic acid are smaller than other AHAs, it can penetrate deeper into the skin to provide its benefits more effectively and to more layers of the skin. 
These benefits include: 



Fights Acne

Blemishes and breakouts are the results of pores that have become clogged. 
As an exfoliator, glycolic acid helps to not only lift dirt and dead skin from the surface of your face but has the ability to get down deeper into hair follicles and loosen up any built-up sebum or proteins that could otherwise lead to more acne. 
And because it helps to clean out your pores, glycolic acid can also help visibly reduce the size and appearance of your pores with consistent use. 

Reduces Fine Lines & Wrinkles 

While it doesn’t have the ability to address deep facial wrinkles, glycolic acid is one method to help soften the visibility of fine lines and wrinkles on your face. 
As it sloughs away dead skin layer by layer, it reveals softer, smoother skin. Check out some of our top anti-aging tips in our related blog article.

Addresses Discoloration

As glycolic acid sloughs away dead skin cells, it also helps to fade any unevenness or discoloration in your skin tone. 
This could include previous sun damage, dark spots, age spots, hyperpigmentation, or acne scars. 
As older skin is removed, new skin that is more evenly pigmented reveals itself, gradually improving the overall appearance of your complexion. 

Increases Product Absorption

A direct result of its exfoliation properties, glycolic acid helps to better prepare your skin for other products to be applied and allows them to be more effective in achieving their designed objectives. 
With all the obstacles, such as dead skin and dirt, out of the way, your skin can better absorb these products. 

Possible Side Effects
Most glycolic acid products that are available for at-home use are quite safe and effective for a majority of the people who choose to use them. 
However, glycolic acid does increase your skin’s sensitivity to sunlight. 
So if you are not good at consistently applying SPF sunscreen, or if you spend extended time by the pool or on the beach, it may not be the best choice for you. 
In these cases, you could also choose to use glycolic acid as a nighttime product to help minimize some of these effects, though your skin will still have some increased sensitivity the next morning. 



As an exfoliator, glycolic acid does come with the risk of causing dry skin. 
You can easily combat this effect by looking for products that include moisturizing ingredients to help offset glycolic acid’s drying effects or applying a moisturizer after use. 

Some people who use glycolic acid will experience a slight tingling sensation when they first start using the product. 
This is normal and should fade with time. But if you experience burning, pain, or itching, you may be experiencing an adverse reaction to the glycolic acid. 
In these cases, wash your face and discontinue use until you speak to your dermatologist or esthetician about the next steps. 



Is Glycolic Acid Right For Me
While glycolic acid seems to be well-tolerated by most people, it is generally mild and safe for most skin types. 
However, it can still be irritating for those with particularly sensitive skin or certain skin conditions, such as eczema or rosacea. 
If this sounds like you, you may be better off using lactic acid, which is a much more gentle skincare ingredient. 



On a positive note, glycolic acid is safe to use during pregnancy unlike many other well-known skin care ingredients such as retinol. 
Although, under these circumstances, you may want to consider using products with concentrations less than 10 percent.



Glycolic Acid Products
Glycolic acid is found in a variety of products from facial cleansers to creams and moisturizers, but each varies widely in the potency of the acid with levels anywhere from 8% to more than 30%. 
However, a higher concentration of glycolic acid doesn’t always mean it is a better product. 
Rather if you are a new user, you should begin with a low potency product to allow your skin to adjust and build up to stronger products over time.

As you introduce new products and increasing strengths, pay attention to how your skin reacts. 
If you start to notice any signs of irritation, cut back on your usage or discontinue it completely. 



Cleansers

Glycolic acid facial cleansers are a really easy way to incorporate this powerful ingredient into your daily routine. 
Simply use it as you would any other cleanser, though it is always best to double check the instructions on the label. 
For daily use, cleansers typically only contain about 8% to 10% glycolic acid as anything stronger may cause too much irritation for the skin. 
A cleanser featuring glycolic acid is particularly good at dissolving dirt and removing oils from the face to reveal softer, smoother skin. 



Toners

Adding glycolic acid through liquid toners, cleansers, serums, and treatments, like Liquid ExfoliKate®—a triple acid resurfacing treatment—is another great way to incorporate some stronger products into your skincare routine as these products typically boast potencies closer to 10% or 12%. 
Because of their strength, they are particularly good at sloughing away dead skin and refining the look of your clogged pores by clearing them out. 
These should only be used once a day, preferably at night. This will help minimize any adverse effects and sun sensitivity. 



Creams & Moisturizers

Using a glycolic acid face cream will give you the benefits of the AHA while adding some moisture to help combat its natural drying effect. 
A glycolic acid cream like the ExfoliKate® Glow Moisturizer reduces the appearance of surface dullness and uneven skin texture while using a combination of AHAs, including glycolic acid, to help loosen and slough away dead surface skin cells. 
At the same time, nopal cactus fruit extract helps to reduce any potential skin irritation caused by the AHAs.
This powerful product resulted in 100% of women showing highly significant improvement in moisturization and 97% of women with highly significant improvement in glowing skin luminosity and radiance after just one use! 



Professional Treatments
There are a number of professional facial treatments, like those at the Kate Somerville skincare clinic, which features glycolic acid at day or medical spas, dermatology offices, or cosmetic surgery practices with the potency of your treatment dictating the type of professional you need to see. 
For example, a superficial chemical peel can be done by an esthetician while a medical doctor is permitted to utilize treatments that go deeper into the skin’s layers. 
If you seek out a professional treatment, it is important that you feel comfortable with your practitioner, thoroughly discuss the risks, and understand what is appropriate for your skin. 
Depending on the results you want to achieve, subsequent treatments may be used with increasing concentrations of glycolic acid, as a series of peels may provide the most significant benefits long term. 



Glycolic acid is a thoroughly researched and very popular skincare ingredient due to its long-standing use within the skin care industry. 
Chances are you already use it in some capacity as part of your regular routine, but if you don’t and would like to introduce it, be sure to take it slow and pay attention to how your skin responds. 
If you try to introduce high concentration products quickly, you will almost certainly end up experiencing adverse effects and irritation.



If you have any questions about the Kate Somerville glycolic acid products, contact us. 
For further questions about which glycolic acid product is right for you, ask your physician or esthetician for recommendations.

Glycolic acid is one of the most popular skin care actives because it works super well at exfoliating the skin while boosting its other functions as well. 
That’s why, even after decades of innovations in the skin care world, with new ingredients coming out on the market and being heralded as total game changers, glycolic acid still reigns supreme. Almost everyone can use glycolic acid as long as they understand how to use it safely.

In this article, we cover everything you need to know about glycolic acid. 
We’ll explain exactly how it works, what kind of products it shows up in, how to choose the right glycolic acid products based on your skin type and skin concerns.

Anything with the word acid in its name might seem intimidating at first, but don’t be fooled, glycolic acid is a naturally-occurring and totally skin-friendly ingredient which is much more likely to clear your acne and brighten your skin than it is to burn your face off. Here’s everything you need to know.  

WHAT IS GLYCOLIC ACID?
Glycolic acid is a chemical exfoliant known as an alpha hydroxy acid (AHA). 
It’s a naturally occuring ingredient derived from plants like pineapple and sugar cane. 
Glycolic acid is the most popular AHA because it’s the strongest, and thanks to its small molecule size has the ability to penetrate skin deeply and easily. 

HOW DOES IT WORK?
Glycolic acid breaks down sebum and the other substances that bind cells together in order to remove dead skin cells and the top layer of skin, so that the fresh, new skin cells of the layer below can shine through. Over-use can lead to redness and irritation, but essentially glycolic acid is suitable for any and every skintype, and is a much gentler alternative to physical scrubs because it won’t tear the skin (which can lead to further long-term damage). 

WHY SHOULD I USE IT?
If your skin looks dull, feels rough, frequently breaks out, or has red marks and scars left behind from spots, then glycolic acid can benefit you.  

Breakouts – Because glycolic acid removes the dead skin cells that block pores, it means that pores are less easily clogged, so you’ll experience fewer breakouts.  

Pigmentation/scars – Glycolic acid also helps with the marks left behind by breakouts – pigmentation only effects the top layers of skin, so with every layer of skin that’s removed, scars will appear more faded and less obvious. 

Dull skin – Skin appears dull and grey when pores are clogged with oil and dead skin, so once these are removed, your complexion will appear fresher and brighter. 

Rough texture – Like physical scrubs, glycolic acid helps to slough away rough and flaky patches of skin. 
It also helps to transfer water molecules from the air to the skin, so it replenishes lost moisture. 

Mature skin – Glycolic acid can help skin that has a lot of sun-induced pigmentation (brown spots). 
It also helps to stimulate the production of collagen – an ingredient which makes skin appear smoother and plumper. 

WHEN SHOULD I USE IT?
In your evening skincare routine – glycolic acid increases skin’s sensitivity to the sun so it’s safer to use it at night time (make sure to wear an SPF the following day). Your skin might need getting used to glycolic acid if you’ve never used it before – it can cause redness and flaking – so start off by using it once a week and gradually increase to see how your skin adapts. It’s also important to be careful what ingredients you pair glycolic acid with – it can cause a reaction if you use it with products containing vitamin A/retinol, so it’s best to avoid layering with other active ingredients. 

Because this is pure glycolic acid, it’s much more effective than those products which combine glycolic with other ingredients, but it’s also more likely to cause a reaction, so should be used carefully to begin with. Of all the products I’ve tried, this has the fasted and most obvious results – clearer, brighter skin in no time at all. 

To apply: After you’ve cleansed, soak a cotton pad in the solution and spend a few minutes sweeping it over and pressing it into skin. 
Allow to fully absorb before applying your serum and moisturiser.

Glycolic acid is an ingredient that typically derives from sugar cane and belongs to the alpha hydroxy acid (AHA) family, alongside other well-known ingredients like malic and lactic acid. Alpha hydroxy acids are a group of natural acids that are commonly found in all sorts of the foods we surround ourselves with. Citric acid, for example, is found in citrus fruits. Lactic acid is found in soured milks and tomato juice, malic acid is found in apples, tartaric acid is found in grapes, and the list goes on. A range of alpha hydroxy acids are used in skincare and cosmetics, mainly because they are believed to be great at helping to treat dry skin, acne and surface wrinkles.

Glycolic acid is the most popular and certainly the most widely studied of the alpha hydroxy acid family. 
Its chemical makeup is small compared to other AHA family members, so it is easily absorbed and able to penetrate skin at a very deep level which makes it an effective at helping to combat a variety of skincare woes. Glycolic acid’s known benefits include its anti-ageing properties, effectiveness in treating acne and its ability to exfoliate the skin while maintaining a natural PH balance. Safe for all skin types, glycolic acid is easy to use and an essential part of any skin-care routine.

How can glycolic acid benefit your skin
There are a few key ways that glycolic acid benefits your skin.

Anti-aging
Because glycolic acid is a small molecule is so small, it has the ability to deeply penetrate the epidermis layer of your skin to stimulate cellular activity. 
This means it’s often added to anti-ageing and anti-blemish treatments in order to hydrate, brighten and tone up your skin. It’s an active smoothing ingredient that evens out the skin’s texture and minimises the appearance of wrinkles by increasing cell regeneration and getting rid of excess dead skin cells to leave skin soft, clean and youthfully fresh. 

Exfoliation
Glycolic acids greatest asset is its ability to help remove the uppermost layer of our skin by breaking down the bonds that bind dead cells together. 
It essentially works to ‘unglue’ skin cells from each other. Breaking this bond creates a chain reaction that, in turn, boosts the cell renewal and turn over, that leaves your skin feeling clean and looking bright. Using glycolic acid in your exfoliation routine helps to keep your skin’s pH level balanced, fade any lingering acne scars and unclog your pores. It’s a truly turbo-charged chemical exfoliant that ensures that your skin reveals itself to be soft and supple. 

Safe for all skin types
Probably because ‘acid’ is in the name, glycolic treatments were once only used on those with oily or acne-prone skin. 
Nowadays, as more and more research has been conducted, glycolic acid is recommended by dermatologists for all skin types, as long as you’re mindful of the formula you’re considering using. Glycolic acid regulates seborrhoea and other difficult to manage skin conditions on young or excessively oily skin and, in opposite effect, both moisturises and brightens mature or dry skin – all depending on the amount of glycolic acid your treatment product contains. (between 2 and 15%). 

Acne busting
Glycolic acid is a great addition to all skincare routines. 
For those who suffer with outbreaks, it’s particularly effective and can fight against a whole range of skin irritation and acne issues. 
Particularly for cystic acne sufferers, it help to unclog even the deepest blockages of dead skin cells and sebum. 
This, when combined with other ingredients in your skincare routine, makes it one of the top options for staving off painful spots. 
Acne scarring is no match for this super AHA either. 
Much in the same way that it is touted as an elixir of youth and a dream exfoliant, glycolic acid can also help to lessen the appearance of deep acne scars. 

Easy to use
What was once a product used in medispas as a part of routine aesthetic medical procedures, glycolic acid is now found in plenty of at-home products – like L’Oréal Paris Revitalift Laser Renew Anti Ageing Glycolic Peel Pads, which are safe for daily use. 
The best part is that the effects of adding glycolic acid into your routine are compound. 
The more frequently you use your treatment of choice – we recommend once a day for a prolonged period – the more effective it will be for your skin. 
It’s an effortlessly simple process that can lead to a multitude of rewards.

The risks involved
As with any and every product you apply or ingest, there are a few key things to look out for that may signal that glycolic acid isn’t for you. 
Sometimes the shoe doesn’t just fit. When you begin a glycolic regimen, be mindful of the changes in your skin, for better and for worse.
As with retinol use, your skin will, in all likelihood, need to get used to glycolic acid before you start to see the benefits. 
Glycolic acid containing skin care formulas will have different concentrations, so be sure to check the percentage before you buy. 
If you have sensitive skin, choose a low percentage formula and work your way up. 
Beginning a glycolic acid routine with a percentage that is too high is more likely to cause redness and irritation.

Be mindful of the other products in your skincare arsenal. 
While each serves its own incredibly useful purpose, make sure you aren’t doubling up on other products containing Vitamin A or AHAs or your skin could become more sensitive, putting you more at risk of environmental damage.

Sun exposure, when using glycolic acid, becomes a much bigger deal. 
It’s incredibly important to wear sunscreen on days when you’re using your glycolic treatments, especially if you are applying them in the morning. 
This is because glycolic acid works to remove the top layer of your skin, putting it at a potentially greater risk of damage and unwanted pigmentation.
Adding glycolic acid into your routine
There are plenty of ways to build glycolic acid-based products into your routine. 
The best way to determine which works best for you, is to determine why you’re interested in using glycolic acid in the first place. 
Here are some ways this powerhouse ingredient can be put to good use:

Glycolic acid helps to reduce acne scarring and inflammation
To help fight acne-prone skin, find yourself a good cleanser that contains glycolic acid. 
We recommend using this cleanser daily either in the morning or just before bed. 
Avoid using it more than once a day – a little often goes a long way.

Clean your skin with your glycolic acid cleanser of choice thoroughly, as you would with any standard facial cleanser. For those looking to pack an extra punch, follow with a glycolic peel toner, like L’Oréal Paris Revitalift Laser Renew Anti-Ageing Glycolic Peel Pads, daily for six weeks.

If you’re not noticing the changes you were hoping for, simply stop treatments for a couple of weeks to give your skin a break and then start a second round of treatment. You can repeat this same treatment until your skin’s inflammation goes down. 
If you do repeat your treatments, giving your skin a break between treatment periods is essential to keep your skin’s natural oils intact.
The last thing you want to do is strip your skin of its ability to protect your itself from free radicals and harmful bacteria.

If you’re more focused on solving acne scarring than actual inflammation, there’s no need to adhere to a daily schedule. 
Committing yourself to a light glycolic acid peel routine once or twice a week will help to reduce scarring and give your skin a healthy glow.

Glycolic acid has a range of anti-aging benefits…
Building glycolic acid-based products into an anti-ageing routine couldn’t be simpler. 
There are a wide range of anti-ageing products that have jumped on the glycolic acid bandwagon, and for good reason.

As mentioned above, when glycolic acid is absorbed into the skin, it makes quick work of separating the ties that hold dead skin cells together. 
This then helps to give your skin a smoother, more youthful appearance. Once skin cells are separated, glycolic acid help to dissolve the layer of dead skin. 
This in turn helps to gently exfoliate, while unclogging pores and allowing new skin to breath.

Beyond allowing fresh skin to rise to the surface, glycolic acid aids in minimising discolouration – a common sign of ageing skin – and helps to stimulate the fresh growth of natural wonder protein: collagen. Now, you’re starting to see why we rave about this miracle molecule.

Applying glycolic acid little and often is favoured over a more extreme approach, and the best way to work glycolic acid into your anti-ageing routine is to add in a simple, low-dose product daily. Incorporating your favourite glycolic acid containing product into your daily routine takes the guesswork out of counting what day of the week your treatment falls on. 
It also saves a costly visit to the dermatologist or medispa for a routine chemical peel.

 

Glycolic acid helps to exfoliate and fight dryness…
If you’re less concerned about acne or wrinkles but find yourself with pesky dry patches or unevenness that you’d like to treat, consider glycolic acid an easy ally to the cause.

We’ve already mentioned all the ways that glycolic acid works to slough off dead skin cells, but did we mention that it also helps to attract moisture from the air, coaxing it into the skin to increase hydration and minimise any additional dryness?
 Not only that, but it’s a great product to use in the morning in the form a cleanser or serum because it helps to prep your skin for other product use. 
It sets your skin up for smearing on your favourite moisturiser and even smoothes your skin, ready for your makeup application.

To use it for exfoliation, consider using it in conjunction with a secondary moisturiser. 
L’Oréal Paris Revitalift Laser Renew Home Peel Kit can be used for a multitude of benefits, including exfoliation and hydration.

The kit contains L’Oréal Paris’s Revitalift Laser Renew Anti Ageing Glycolic Peel Pads and L’Oreal Paris’s Laser Renew Advanced Anti Ageing Care SPF 20. 
The former of the two products contains ready-to-use glycolic acid pads that are perfect for incorporating daily exfoliation into your routine. 
The second product is all about protecting your fresh new skin cells from the harmful effects of UVA/UVB rays. 
This cream is enriched with a 3% concentration of Pro-Xylane™ and LHA, all wrapped up in a triple action formula that when combined helps to refirm, refine, and shield your skin from damage. 
A kit like this is perfect for daily use. 
We’re pretty sure you’ll notice a transformation in your skins luminosity and smoothness in no time at all.

What to consider when using glycolic acid
Beyond these more specific routines, there are a few other things you might like to consider when choosing the glycolic product that works best for your skin type. 
Night creams should be progressively applied. 
Begin using them once a week, followed by every 3 nights if your skin responds well to the initial inclusion in your regimen. 
Peeling treatments can be applied once or twice a week for a gentle, exfoliating action. 
They don’t necessarily need to be used every single day to be effective. 
In many cases, less is more. 
Dermatologists use higher concentrations of glycolic acid (20 to 70%) to remove several layers of skin over a short, set period of time. 
In your at home products, lower concentration glycolic acid products used over a more frequent period of time have been shown to be just as effective. 
It’s all about what works best for you, your skin type, and your routine

The benefits of glycolic acid
We’ve thrown our knowledge on the table. 
Now it’s up to you to discover the benefits of incorporating glycolic acid into your routine first hand. 
Learning the ins and outs (and science behind!) skincare like this can often feel overwhelming. 
Glycolic acid has an unbelievable number of skincare benefits – so many, in fact, that it’s been labeled a “miracle product.” 
We know there’s no such thing, but here are a few benefits of incorporating glycolic acid into your daily skincare routine:

Glycolic acid works across the board as an anti-ageing product. 
It removes excess and dead skin cells, it boosts cell turnover (which in turn decreases the dips that form wrinkles) and it is an active cheerleader of collagen production, spurring it on from first use.

Glycolic acid actively helps to combat active acne inflammations at the exact same time as it works to reduce previous acne scarring. 
This one-two punch makes it a favourite of acne sufferers the world over.

Glycolic acid is an exfoliation expert. 
It’s easily absorbed into the skin and because it unbinds dead skin cells from healthy new ones, it releases and removes dry patches with expert precision. It’s also highly hydrating. These two powers combined and it’s unstoppable (especially in the winter).

Glycolic acid-based products are incredibly easy to find on your local skincare shelf and these products offer something for everyone. 
Consider your needs when choosing what routine will work best for your needs, there’s very little user error to be found here – just make sure there’s not too high of a concentration for your skin’s sensitivity level.

Glycolic Acid: What It Is and Why You Should Use It
Daily environmental damage and simply getting older impair our skin’s natural ability to renew itself as it once did, which leads to a buildup of dead, dull surface skin. Routine use of a leave-on glycolic acid exfoliant is one of the most important steps to keep skin looking youthful, vibrant, and radiant now and into the future.

While there are different kinds of AHAs – lactic, malic, citric, and tartaric acids – by far, the one with the most long-term research proving its effectiveness is glycolic acid.

Glycolic Acid Benefits
Using an exfoliant with glycolic acid for your face results in a brighter, more even toned complexion. Like all AHAs, glycolic acid works by helping turn over spent cells on skin’s surface.

This type of exfoliation addresses numerous skin concerns, including sun damage, uneven tone, rough, flaky patches of skin, fine lines, and wrinkles. 
In higher concentrations, glycolic acid can even improve the look of deeper wrinkles.

Studies also show that glycolic acid significantly increases skin’s hydration. 
It does this by helping skin make substances like mucopolysaccharides, which help skin stay hydrated by increasing its natural content of hyaluronic acid, which in turn enhances skin’s resilience.

One exciting new note about glycolic acid: emerging research shows it might even protect skin against UV damage (in addition to reducing its damaging after-effects), though more studies need to be done and of course it doesn’t replace the need for sunscreen. Still, it’s a promising development!

Glycolic acid occurs naturally in sugar cane, but is most effective when synthesized in a lab, where its potency and concentration are optimized for use in skin care. 
Using plant sugars, like sugar maple, for their glycolic acid content is an option, but the bulk of the research on glycolic acid’s benefits for skin is about the synthetic form, because this type can be optimized for effectiveness, purity, stability, and pH, all critical to getting effective glycolic acid products.

Is Glycolic Acid Right for Me?
When selecting a leave-on exfoliant, should you choose one with glycolic acid, or get a salicylic acid exfoliant, also known as a beta hydroxy acid, or BHA exfoliant?

While there are similar benefits (such as restoring skin’s radiance, hydrating, and reducing many signs of aging), the two are different enough that skin type and concerns matter. Water-soluble glycolic acid exfoliates at skin’s surface (as does salicylic acid), but oil-soluble salicylic acid (BHA) also penetrates further into pores, making it better for clog-prone, oily skin. BHA also has redness-relieving properties, so is the type to choose if that’s one of your concerns.

Can’t decide? It’s fine to use both types of exfoliants as part of your skin care routine – you can use them at the same time, alternate days of usage, or use one in the morning and one at night, depending on your preference.

Glycolic Acid Exfoliants
While glycolic acid is a time-proven AHA, not all glycolic acid exfoliants are created equal. 
In order for you to experience best results, it has to be carefully formulated.

First, it should be formulated at a pH between 3 and 4, which is considered the optimal range for it to exfoliate. 
Concentration matters, too; amounts between 5 and 10 percent of glycolic acid are ideal (though there are more intense, rinse-off peels with higher concentrations of AHAs you can use at home).

All skin types can benefit from using a weightless glycolic acid gel to revitalize skin tone and reveal smoother, firmer-looking skin.

If you’re looking for something more powerful to tackle deeper wrinkles, dullness, and stubborn signs of sun damage, we recommend using a glycolic acid serum that works well over and under other skin care products so you can add it seamlessly into your routine.

Glycolic acid isn’t just good for your face. A fragrance-free exfoliating body lotion is the perfect way to get smoother skin all over. 
Using a glycolic acid lotion once a day results in hydrated, younger looking skin on arms, legs, elbows, and knees with a creamy-yet lightweight feel that’s never greasy.

Glycolic Acid
Glycolate is an intermediate of photorespiration and thus is much higher in content in plants than in animal tissues

Glycolic acid is a AHA (Alpha Hydroxy Acid) and has the smallest molecules within that group meaning it can penetrate deep into the skin. It exfoliates to remove the outer layer of dead cells and sebum, restoring the pH level of the skin and leaving behind a smoother surface.

It encourages skin cell renewal and removes dirt, sweat, oil and sebum that are clogging pores, this helps to treat acne, blackheads, pigmentation and oiliness.

It smoothes the look of imperfections leaving a more even-toned complexion and revealing fresh, bright, glowing skin. 
Glycolic acid has been found to increase collagen production and helps to plump and moisturise skin through its water-binding abilities.

The result is that skin will appear clarified and smooth which helps to diminish the appearance of wrinkles and fine lines. 
By removing the outer layer of dead dull skin cells not only does Glycolic acid help skin to appear brighter and younger looking it also enables other products in your routine to penetrate deeper into the skin.

Unless you’ve been on a social media diet, you’ve likely come across glycolic acid in your newsfeeds quite often. 
It’s long been a mainstay in dermatologist offices, recognized as an effective anti-aging resurfacing ingredient for evening skin tone and reducing the appearance of wrinkles and dark spots. But the interest in glycolic acid for everyday use has spiked in recent years. 
As such, if you’re on the hunt for a new skin care product to add to your daily regimen, you have plenty of options formulated with this popular ingredient that you can choose from, ranging from facial cleansers to moisturizers to serums. But what if there are glycolic acid benefits you’re missing out on? 

WHAT IS GLYCOLIC ACID?
First things first, if you’re new to this ingredient, let’s define. 
According to the U.S. Food & Drug Administration, glycolic acid is one of the most common alpha hydroxy acids (AHA) used in cosmetics. 
And in case you need a refresher, according to the Mayo Clinic, AHAs are a substance that can help exfoliate dead skin cells from the surface of your skin. Per the American Academy of Dermatology, AHAs can even contribute to the appearance of younger-looking skin. 
It’s why this powerhouse exfoliator consistently makes the list of best anti-aging ingredients to add to your skin care routine. The U.S. National Library of Medicine states that in addition to resurfacing the skin and evening skin tone, glycolic acid can also minimize the appearance of wrinkles. 

HOW TO ADD GLYCOLIC ACID TO YOUR SKIN CARE ROUTINE
Before you start using a whole bunch of skin care products formulated with glycolic acid, listen up. 
Alpha hydroxy acids like glycolic acid can increase your skin’s sun sensitivity, so you’ll need to take sun safety and protection seriously. 
The FDA recommends using sunscreen, wearing protective clothing, and limiting sun exposure, which means seeking out shade and avoiding the sun during its peak hours.

Using a glycolic acid serum is one of the best ways to experience the benefits of this popular ingredient, as face serums tend to have high concentration levels. 
Try the L’Oréal Paris Revitalift Derm Intensives 10% Pure Glycolic Acid Serum, formulated with 10 percent pure glycolic acid and aloe (to help soothe the skin and make it suitable for daily use). To use it, apply four to five drops to clean, dry skin every evening before moisturizing—don’t forget to use SPF in the morning! 
For sensitive skin, start by using two to three times per week and build up to nightly use. 
In just one week, your skin will be resurfaced and younger-looking. 
Over time, your skin tone will be more visibly even, and dark spots and wrinkles will be visibly reduced.

OUR BEST PRODUCTS FORMULATED WITH GLYCOLIC ACID
Beyond adding a serum to your routine, if done correctly, you can create a whole routine of skin care products formulated with glycolic acid to help you get your most beautiful complexion.

L’ORÉAL PARIS REVITALIFT DERM INTENSIVES 3.5% GLYCOLIC ACID CLEANSER
This cleansing gel removes makeup, excess oil, dirt and impurities from the skin’s surface while revealing smoother, brighter skin. 
It’s the perfect way to cleanse your face at night before applying the L’Oréal Paris Revitalift Derm Intensives 10% Pure Glycolic Acid Serum.

L’ORÉAL PARIS REVITALIFT BRIGHT REVEAL BRIGHTENING DAILY SCRUB CLEANSER
This daily facial cleanser is formulated with gentle micro-pearls to exfoliate dullness and impurities from the surface of skin. 
Immediately, skin looks brighter, while skin tone appears more even with continued use over time.

L’ORÉAL PARIS REVITALIFT BRIGHT REVEAL BRIGHTENING DAILY PEEL PADS
These multi-ply textured pads physically remove dead skin cells from the surface of the skin. 
Immediately, skin looks brighter and feels softer, while skin tone is more even and texture more refined with continued use over time. Use nightly on clean skin. 

L’ORÉAL PARIS REVITALIFT BRIGHT REVEAL BRIGHTENING DAY MOISTURIZER SPF 30
Formulated with Pro-Retinol and vitamin C (along with glycolic acid, of course) this daytime moisturizer immediately makes skin appear brighter, while dull, uneven skin tone is renewed with continued use over time. This moisturizer is also formulated with SPF 30, so apply as directed, and don’t forget about the other sun protection measures you should be taking daily

This chemical exfoliant is an alpha-hydroxy acid—the family of water-loving acids that works on the surface of the skin. 
Naturally derived from sugar cane, glycolic acid “dissolves the bonds that hold dull, dead skin cells on the surface of the skin so the skin will gently shed,” according to board-certified dermatologist Hadley King, M.D. Basically, glycolic acid (and all AHAs, for that matter) loosen dead skin cells that sit on the topmost layer of the skin, paving the way for soft, smooth skin underneath.  

But here’s the thing about glycolic acid: It has the smallest molecular weight of all the alpha-hydroxy acids, which means it can penetrate the outer layer quite easily (unlike its AHA counterpart, lactic acid, which is larger in molecular size). 
Meaning, it does its work rather quickly—leading to fresh, rejuvenated skin that’s soft to the touch.

As mentioned, glycolic acid is the workhorse in exfoliating products. 
It unglues dead skin cells from the topmost layer, but it also provides moisturizing qualities as well. 
That’s what makes glycolic acid so great: It strikes a unique balance as it “can be simultaneously exfoliating and hydrating, making them very beneficial to many skin types,” board-certified dermatologist Mona Gohara, M.D., tells us about AHAs in skin care. 
The best skin types, however, might just be those with normal to dry, sun-damaged skin. (If you have very sensitive skin, we might suggest a lighter exfoliator like lactic acid or fruit enzymes.) Here are some of the highlights:

Decreases hyperpigmentation: Because it works on the surface (rather than penetrating into the pores; that’ll be your BHAs), glycolic acid can slough off pigmented skin and encourage cell turnover. That makes it great for skin care concerns like hyperpigmentation and discoloration, according to King. 
The research backs it up, too: A systematic review of glycolic acid’s effects on photodamage and hyperpigmentation showed that glycolic acid peels led to significant improvements in pore size, rhytids (meaning wrinkles), and radiance. 
Reduces the appearance of photodamage: One study on the exfoliant’s photoprotective effects even showed that UVB-burned skin healed sooner when treated with glycolic acid for seven days—a reason the acid is perfect for those facing some sun-damaged skin, King says.
Reduce the appearance of acne scars: Another study on glycolic acid’s ability to treat acne scars showed that the exfoliant is superior in reducing the appearance of those scars; even low-strength daily products were shown to be effective, especially for patients who can’t tolerate an intense chemical peel. 
Supports skin elasticity: “Studies have shown that six months of topical glycolic acid stimulated a 27% increase in epidermal thickness,” King explains. 
As we age, our skin’s natural cell turnover process decreases, but exfoliating with glycolic acid can help rejuvenate those skin cells and contribute to plump, fresh-looking skin (in other words, say goodbye to that tired, dull appearance).
While people suffering from blackheads may fare well with glycolic acid as well (after all, those plugs are more surface-level), reach for glycolic acid if discoloration, scarring, and fine lines are your main gripes. No matter what, regularly exfoliating your skin has its benefits—it improves skin texture, enhances collagen production, and allows other ingredients to better penetrate the skin, says King. 

 How to use it in your routine.
Take a peek into your skin care arsenal, and chances are you’ll find a product featuring glycolic acid. 
It’s one of the more researched AHAs, which is why you can find it in many clarifying formulas—namely, cleansers, toners, serums, and renewal masks, according to board-certified dermatologist and founder of MMSkincare Ellen Marmur, M.D.

Other popular products are those premedicated pads (the beloved gly-pad, if you’ve heard your derm toss the term around), known for removing sweat and residual makeup if a full-on cleanse feels like too much—after a workout, perhaps. 

In terms of procedures, that’s where peels come into play: A glycolic acid peel is one of the most common AHA peels used in dermatologists’ offices. 
That said, it’s not a venture you should take on in the comfort of your own home: “In a clinical setting, doctors generally use a glycolic acid peel that is 40 to 50% glycolic acid,” says King, whereas an at-home product will likely have a 10 to 20% solution. That’s because trained professionals can take one look at your skin and know whether it could benefit from that heavier exfoliation or whether you should stick to a clarifying cleanser and call it a day. 

That said, it’s best to take it slow with glycolic acid (and all exfoliating products, for that matter) until you know just how your skin is going to react. 
As always: Do a patch test before applying new products to the face.

Anyone who shouldn’t use it? 
Because glycolic acid has a smaller molecule size (and can penetrate more easily into the skin), that means it’s a little more heavy-duty than some of the other sensitive-skin-approved ingredients. While AHAs in general are great for most skin types, glycolic acid can be a bit unfavorable for some folk. 
“Very sensitive skin may find glycolic acid irritating,” King says. That said, those who suffer from sensitive skin conditions like eczema or rosacea might want to proceed with caution or consult your dermatologist before giving it a go, says Marmur. If you swipe a gly-pad over your skin and get some redness or discomfort, you might want to consult your derm before using it again (or perhaps swap it for even gentler lactic acid).  

Those with oily skin prone to acne and clogged pores might also fare better with a BHA (like salicylic acid) over this AHA. 
Again, both are great gentle exfoliants, but if you’re looking for a product to penetrate clogged pores (say, if you suffer from deep, cystic pimples), oil-soluble BHAs might be a better fit for those skin care woes. 

The bottom line.
Looking for gentle exfoliation to help fade acne scars, hyperpigmentation, and decrease fine lines? 
Glycolic acid is the solution
It’s best to consult your derm before diving right in, but generally speaking, glycolic acid can be a lovely addition to your skin care arsenal; especially those in the market for sensitive-skin-approved formulas, consider this AHA your newest go-to. 

Glycolic acid may not be anything new—it’s common in skin care products and in-office chemical peels—but not everyone knows how effective it can be as part of a regimen. 

What Is Glycolic Acid?
“Glycolic acid put skin care on the map in the ’90s,” says board-certified, Beverly Hills–based dermatologist Dr. Vicki Rapaport, M.D. 
“It was the first ingredient that was either incorporated into a take-home cream or done in a peel that actually did anything without breaking the bank or requiring anesthesia.”

A derivative of sugarcane, glycolic acid is an alpha hydroxy acid (AHA), a group of naturally occurring “fruit acids” that can be found in foods. 
AHAs work by loosening the glue-like substance that holds dull and dead skin cells on the topmost layer of your skin, revealing newer, healthier skin. 
It also stimulates new cell generation, resulting in improved skin texture, tone and a brighter complexion. 
And because glycolic acid has the smallest molecular size of all the AHAs, it’s the most bioavailable and active, allowing it to penetrate the skin the most easily.

But that’s not all. Aside from providing instant rejuvenation, glycolic acid has also been shown to stimulate the production of collagen and elastin, which means that with continuous use, glycolic acid can actually accelerate skin healing and reduce signs of environmental damage.

What Else Does Glycolic Acid Do?
Some dermatologists also favor glycolic acid over other acids to improve skin issues like blackheads, hyperpigmentation, enlarged pores, psoriasis, keratosis pilaris and hyperkeratosis, among others. It also removes excess oil, just as it relieves dry and scaly skin conditions. 
“In my experience,” says dermatologist Dr. Michelle Henry, “I find it to be more effective and with fewer side effects than other acid.”

How to Use Glycolic Acid
Now that you know how glycolic acid works, the next step is to find a way to make glycolic acid work for you. 
Of course, nothing beats a visit to your dermatologist or esthetician’s office for a series of professional peels, but maintenance at home is crucial!

What Is Glycolic Acid?
Have you been searching for a skincare ingredient that minimizes and unclogs pores and fights the signs of aging at the same time? 
Then it’s time you learn about glycolic acid, one of the most sought-after ingredients in the skincare industry. 
Here’s how glycolic acid works and why you should incorporate this versatile ingredient into your skincare routine.

What is glycolic acid?
Glycolic acid is a commonly used alpha hydroxy acid (AHA) that’s derived from sugar cane. 
Alpha hydroxy acids (AHAs) are synthetically derived versions of naturally occurring, non-toxic fruit acids. 
AHAs are used in many skincare formulas and, out of all the AHAs, glycolic acid has the simplest structure, is the smallest, and possesses the lowest molecular weight. 
That makes it easy for glycolic acid to penetrate the skin, making it incredibly effective.

What does glycolic acid do?
So what exactly does glycolic acid do? One word: exfoliation. 
An AHA removes dead skin cells so they can’t mix with sebum and clog your pores. 
Think of glycolic acid as a superpower exfoliator that helps keep skin healthy by ensuring your pores are gunk free. 
Glycolic acid is also effective at helping to improve the appearance of acne scars and dark spots because it helps shed those dead cells and refresh the skin’s surface.

Can anyone use glycolic acid?
It’s important to understand how to use glycolic acid, especially if it’s your first time. 
There are different glycolic acid uses, so depending on what type of topical product you’re using, always conduct a patch test first to make sure your skin can tolerate it.

Apply glycolic acid in the evening because it will make your skin more sensitive to the sun. 
There are other benefits to applying glycolic acid at night, since nighttime is when your skin repairs itself — up to three times faster than during the day! 
As you catch your zzz’s, the skin is more permeable and more receptive to glycolic acid’s healing properties.

What are the benefits of glycolic acid?
Glycolic acid boosts your skin’s natural exfoliating process and helps your skin retain moisture. 
Why is this important? 
Because when acne-prone skin gets too dry, the body will overproduce oil to compensate. 
More oil means a more fertile environment for new acne breakouts.
 Glycolic acid’s extra moisture boost also counterbalances the dryness that can sometimes come from using benzoyl peroxide and salicylic acid, two ingredients often found in acne treatments.

But that’s not all. Glycolic acid can also tackle telltale signs of aging. 
Because glycolic acid molecules are the smallest out of all AHAs, they can penetrate deep into your skin and create quite an impact. 
The acid stimulates collagen production, which may help soften fine lines and wrinkles while making the skin look and feel more toned, even, and radiant.

Are there any side effects of glycolic acid?
All alpha-hydroxy acids can mildly irritate sensitive skin, but in concentrations less than 10% (what you’ll find in most skincare products), most people don’t have issues. 
However, if you start to experience redness, peeling, or irritation, reduce application to 2-3 times a week until your skin builds up tolerance. 
If any of that irritation persists, make sure you stop using the product and consult your doctor.

When it comes to using glycolic acid with retinol or another acid, it’s possible that using both at once may be too much. 
Consider applying glycolic acid one night and retinol or lactic acid the next and continuing to switch between them. If you do use both simultaneously, keep an eye on your skin. 
If it starts to peel or become irritated, it’s a sign you’re overdoing it.

No matter how often you use glycolic acid, always wear sunscreen any time you go outside because it can make your skin extra-sensitive to sunlight.

Glycolic acid products
While salicylic acid and benzoyl peroxide may be the two most recognized acne-fighting ingredients, glycolic acid products rank right beside them in importance. 
It’s a super-exfoliator that gets rid of dead skin cells so they can’t clog your pores. The hydration and healing qualities of glycolic acid help with the appearance of post-acne marks and discoloration and keep your skin smooth, resilient, and healthy-looking.

Glycolic acid products for dry skin
Exfoliation is an essential step in your skincare routine. 
AHA (glycolic acid) exfoliants gently remove the top layer of dead skin cells, helping to reveal the healthy layer of skin underneath. 
If you have normal to (very) dry skin, many exfoliants can be a no-go, leaving skin drier and more irritated than before. 
However, the ingredients in AHA glycolic acid products are much gentler than other products that exfoliate your skin, such as a scrub. 
AHA products are the fastest way to reveal soft, smooth, radiant-looking skin.

Daily use of a glycolic acid exfoliator will enhance the effectiveness of the other products in your routine as they will be absorbed faster because they don’t have to penetrate a layer of dead skin cells first.

How do AHA (glycolic acid) exfoliants work? 

Different types of AHAs
BHA exfoliants clean deep inside your pores while AHA exfoliants mainly work on the skin’s surface making them particularly suitable for dry skin. 
This helps the skin to hold onto more moisture. There are various alpha hydroxy acids (AHAs): glycolic acid, lactic acid, malic acid, tartaric acid, citric acid and mandelic acid

 
Glycolic acid (hydroacetic acid or hydroxyacetic acid); chemical formula C2H4O3 (also written as HOCH2CO2H), is the smallest α-hydroxy acid (AHA). 
This colorless, odorless, and hygroscopic crystalline solid is highly soluble in water. 
It is used in various skin-care products. 
Glycolic acid is found in some sugar-crops. 
A glycolate or glycollate is a salt or ester of glycolic acid.

Formula: C2H4O3
Net Charge    0
Average Mass    76.05136
Monoisotopic Mass    76.01604

Chemical Role(s): Bronsted acid
A molecular entity capable of donating a hydron to an acceptor (Bronsted base).
(via oxoacid )

Biological Role(s): metabolite
Any intermediate or product resulting from metabolism. The term ‘metabolite’ subsumes the classes commonly known as primary and secondary metabolites.

Application(s):    keratolytic drug
A drug that softens, separates, and causes desquamation of the cornified epithelium or horny layer of skin. 
Keratolytic drugs are used to expose mycelia of infecting fungi or to treat corns, warts, and certain other skin diseases.
 
glycolic acid has functional parent acetic acid 
glycolic acid has role keratolytic drug 
glycolic acid has role metabolite 
glycolic acid is a 2-hydroxy monocarboxylic acid 
glycolic acid is a primary alcohol 
glycolic acid is conjugate acid of glycolate 

Incoming    
2-phosphoglycolic acid has functional parent glycolic acid 
caffeoylglycolic acid methyl ester has functional parent glycolic acid 
glycolate ester has functional parent glycolic acid 
phenoxyacetic acid has functional parent glycolic acid 
phosphoglycolohydroxamic acid has functional parent glycolic acid 
ureidoglycolic acid has functional parent glycolic acid 
glycolate is conjugate base of glycolic acid 

Glycolic acid is an alpha hydroxy acid (AHA) that dissolves the bonds between dead skin cells on the face, allowing them to be wiped away easily, revealing smoother and younger skin.
It is a common face ointment for most women aged 30-35 years. 
Now, the important thing to remember is, glycolic acid comes in various concentrations.

It is OK to use 1-2% containing glycolic acid face wash or ointments daily. 
The creams have a higher glycolic acid content (10% and above) and must only be used once or twice a week to avoid skin irritation. 
The creams with a concentration above 15% may need to be kept only for a few minutes and then wiped off.

Any cleanser with a glycolic acid content of more than 20% should be used under professional guidance. 
Using these products at home may cause complications, such as severe skin rash or even skin burn.

What is the role of glycolic acid in skincare?
Glycolic acid is a naturally occurring fruit acid belonging to the group of alpha hydroxy acids (AHA). 
It is derived from sugarcane. Being the smallest alpha hydroxy acid (AHA), glycolic acid can easily penetrate the skin and function effectively. 
Glycolic acid mostly suits everyone with oily and acne-prone skin. Its regular use in the skincare regime comes with the following benefits:

Exfoliation:
Dead skin cells pile up on the top layer of your skin over time and make your skin look dull. 
This process increases with aging and due to frequent exposure to the sun. Glycolic acid clears up this layer of dead cells, speeds up the skin renewal process, and smoothens your skin.

Anti-aging:
Glycolic acid improves the collagen content of your skin, thickens the outer layer of your skin, and acts as anti-aging. 
It makes the skin appear plumper and even in texture.

Anti-acne:
Glycolic acid acts as an anti-clogging agent by clearing up the excess oil and dead cells that block the pores of the skin. 
It also has minor action against Propionibacterium acnes, a bacterium that causes acne. These actions help in preventing further acne breakouts.

Skin lightening:
Glycolic acid clears the uneven pigmentation, lightens your skin, and reveals your natural color.

Better absorption of other skincare products:
Glycolic acid preps your skin and boosts the absorption of other skincare products, such as acne creams, serums, skin lighteners, and moisturizers.

Glycolic Acid (or hydroxyacetic acid) is the smallest of the alpha-hydroxylised acids, better known as AHA or multi-fruit acids. 
It may be extracted from “sugared” vegetables (sugar cane, beetroot, grapes …) or may be synthesized. 
In cosmetics, most often, the synthetic product is used.

Magic peeling
Glycolic Acid main property is to be keratolytic: by simple contact, without rubbing, it interacts with keratin, weakens and/or destroys the lipid nods between the stratum corneum cells (the outer layer of the epidermis) to get rid of dead cells faster than by natural desquamation.

Results: it tightens pores, smoothes the skin, helps even complexion, makes wrinkles, spots and other unflattering marks, such as acne scars, less visible. 
Thus, it is known to improve the well-being of oily skins, as well as of mature or “tired” skins.

Another peculiarity: by getting the skin rid of dead cells, it “opens the doors” of the skin, and eases the penetration of other active ingredients of cosmetics (vitamins and other anti-oxidants, moisturizers …).

The optimum dosage
Too often, the importance of the dosage of an active ingredient in a cosmetic is not looked at.

Glycolic Acid is a good example: if used at less than 5% in the finished product, it is a moisturizer. 
At more than 8%, its exfoliating action begins, and increases with its concentration.
Cleansing gels, purifying creams designed for combination and oily skins, or anti-ageing and complexion brightening cares may contain between 8% and 20% of Glycolic Acid.

Though there is no limit set by any regulation, there is a consensus on a 20% figure as the reasonable limit for cosmetic applications. 
Exfoliations performed in beauty parlours should not use higher concentrations, while those made by dermatologists may go up to 70%, even 90%. 
Protocol of care is based, then, on treatments lasting several weeks, with a progressive increase of the content of Glycolic Acid along the time, obviously, under medical control.

Prickling, irritating, sensitizing
Given its course of action, using glycolic acid does not come free of any inconvenience, even some undesirable effects.

Dr Marie-Pierre Hill-Sylvestre, a dermatologist and one of the experts of Cosmeticobs-L’Observatoire des Cosmétiques , warns, “Glycolic Acid prickles on contact. 
The patient shall get this information before any treatment. It has a kind of scrubbing action on skin, which makes it more sensitive to sunrays, to irritant cosmetics such as exfoliants, to local medical treatments, such as those based on retinoic acid (acidic Vitamin A).”

Too harsh or too high in Glycolic Acid, peelings may increase the risks of photosensitization (reaction to UV radiation) and irritations of the epidermis, or make it more brittle.

This, especially if the pH of the exfoliating products is not in the right range. 
This is a major factor in the aggressiveness of Glycolic Acid toward our skin, as Dr Hill-Sylvestre explains, “Apart from the Glycolic Acid concentration, the pH of the solution is important to define its aggressiveness. The lower, the more the product is acidic, the more it is irritant.”

This information should be taken into account before buying the product … but it is rarely written on labels.

A difficult assessment of the safety
The question of the safety of AHA for use has been surveyed by the then Scientific Committee on Cosmetic products and Non-Food Products (SCCNFP), now the Scientific Committee on Consumer Safety (SCCS). 
In 2000 and in 2004 , this committee fingered out the lack of data to evaluate several points:
• their long-term safety,
• their would-be damages toward the barrier-function of the stratum corneum,
• their effects on the cutaneous absorption of other cosmetic ingredients,
• their effects on the skin reaction to UV radiation.

Lacking relevant data to release a full evaluation on the safety on these ingredients, the SCCNFP only gave the opinion that using Glycolic Acid up to 4% in solutions with a pH ≥ 3.8, was safe.
It suggested to issue, later (but not yet done nowadays), a regulation that would set restrictions or limits to the usage of Glycolic Acid.

Nevertheless, its opinion came with a recommendation, stating the warnings that should be given consumers:
• Avoid contact with eyes.
• Avoid UV radiation, or use a protection against UV radiation, when applying products containing AHA, as AHA may increase their harmfulness.

Hardly reassuring …

Final warning
Up to now, AHA, hence Glycolic Acid, have not to comply with any restriction for use in cosmetics in Europe. 
The consumers’ safety is entirely up to the manufacturers, who must establish which pH and concentrations of the active ingredients will lead to an acceptable tolerance.

Is this enough? No, if one trusts in what is written in some forums on the Internet, or when one looks at some products available on some websites. 
The fight against wrinkles, for an even, spots-free complexion, attracts many people. 
The demand for high-in-Glycolic-Acid products to make one’s peeling at home is strong.

No individual recipe should be used! A stronger efficiency may have dramatic effects on skin. 
Carefulness and reason are better than burns and irritations: any application of a product containing more than 20% of Glycolic Acid shall be performed and followed only by a dermatologist.

Benefits Of Glycolic Acid
1. Exfoliation
Our skin has keratinized dead layers of skin cells that reach the topmost surface and are shed there. 
There can be a dead skin cell buildup due to lack of proper cleansing, exfoliation, sunlight and age. Such an accumulation of dead skin cells can lead to dull and aging skin. 
Glycolic acid is an excellent exfoliant [2] that gets rid of the top layer of the skin to reveal a fresh layer.

2. Anti-aging
Think anti-aging, think glycolic acid. 
Glycolic acid helps to boost collagen levels in the skin. 
Collagen is a fibrous protein found in the dermis and keeps the skin firm. Diminishing levels of collagen can lead to sagging skin, fine lines and wrinkles.

3. Humectant
Glycolic acid is also a humectant and this property makes it a best fit for moisturizers when used in low concentrations. 
t can draw moisture from the air and lock it in the skin.

4. Acne fighting properties
Acne-prone skin can benefit from glycolic acid. 
Acne is caused when hair follicles on your skin get clogged with excess oil, dirt, dead skin cells and bacteria. 
Glycolic acid removes the dead skin cell build up and can improve your acne over time.

5. Preps up the skin for other products
Due to its exfoliating properties, glycolic acid enables the skin to absorb skin care products. 
After achieving a smooth skin with glycolic acid, your skin is now ready for a dose of acne creams, anti-aging serums or a vitamin boost serum.

How To Use Glycolic Acid On Skin?
Glycolic acid is found in most chemical peels that treat skin concerns like acne scars, dark patches, melasma and age spots. 
It can be used in your skin care routine in the form of cleansers, peels and creams. 
Products containing glycolic acid can address pigmentation issues, scarring, fine lines and wrinkles.

Who Can Use?
Glycolic acid is suitable for all skin types. 
Primary function of glycolic acid on skin is exfoliation, which refers to some level of irritation. 
If you have sensitive skin, consult your dermatologist before using glycolic acid. 
People with darker skin tones might have a risk of pigmentation with the use of glycolic acid.

How Often Can You Use?
The answer to this will be based on your skin type, age and skin’s tolerance level. 
Start small and increase it if your skin is reacting positively. 
It also depends on the kind of glycolic acid product you’re using. 
A cleanser with a lower percentage of glycolic acid can be used everyday. 
A cream with a higher level of glycolic acid can be used once daily.

Will Glycolic Acid Work For My Skin Type?
Glycolic acid is highly effective if you have normal, oily or combination skin types. 
But if you have dry and extremely sensitive skin, it may not be for you. 
People with sensitive skin have a high chance of reaction with glycolic acid.

Is It Ok To Use Glycolic Acid Everyday?
You may use skin care products containing glycolic acid in strength of 10% everyday. However, glycolic acid peels contain 20-30% of the active and should be used once every 6 months.

What Are The Side Effects Of Glycolic Acid?
Most at-home glycolic acid products are safe and effective. 
However, it can lead to dryness. 
So follow it up with a good moisturizer.
Skip glycolic acid products if you think you will be exposed to sunlight for a very long time on a particular day. 
Glycolic acid makes the skin susceptible to damage. Never forget to use sunscreen.
Be prepared for a slight tingling sensation that disappears after a point.
What Ingredients Shouldn’t Be Combined With Glycolic Acid?
Do not mix vitamin C and glycolic acid as vitamin C will lose its efficacy in this combination.
Avoid using vitamin B3 with glycolic acid. 
Vitamin B3 needs a neutral pH to work effectively, while glycolic acid has a low pH level.
Refrain from using retinol with glycolic acid.
What To Consider Before Turning To Glycolic Acid?
To know how well your skin can take glycolic acid, try using it in low concentrations at first. Higher strengths may cause redness and flaking.
If you spot flaking during the initial days of use, do not pick at your skin. 
This may cause scarring and hyperpigmentation.
Like any other alpha hydroxy acid, glycolic acid makes your skin more sensitive to the sun. 
Use of a good sunscreen becomes mandatory.
Are you going to try this recent skin care innovation? Talk to your dermatologist and include it in your routine to up your skin care game.

Glycolic Acid for Household Cleaning

A Premier Ingredient for Bathroom and Kitchen Acid-Based Cleaners and Detergents
Cleaning and disinfecting hard surfaces in homes, hotels, and restaurants present their own unique considerations. 
Traditionally, these spaces feature items that can’t be removed for thorough cleaning, such as:

Ceramic tile
Grout
Porcelain tubs, sinks, and toilet bowls
Counter tops
Shower doors and stalls
Glycolic acid from Chemours facilitates the balance between efficacy and safety in cleaning formulations. Chemours glycolic acid’s attributes include:

Excellent cleaning capability
Low toxicity, volatility, color, odor, and corrosiveness
Nonflammable
High water solubility
Biodegradability
Chemical stability
Chloride and phosphate free
How Glycolic Acid Enhances the Efficacy of Household Cleaning Agents
Because glycolic acid has wide compatibility with a range of ingredients like surfactants, biocidal agents, corrosion inhibitors, fragrances, and dyes, it’s easy to formulate an effective cleaner that is safer and more environmentally sound than a mineral acid-based cleaner. 
Glycolic acid works on its own or in blends with other acids in cleaning formulations. 
Its unique properties include:

Low pKa and molecular weight, which increases its efficacy on hard water scales
Effectiveness solubilizing inorganic scale
Low corrosivity on household surfaces
High efficiency at complexing calcium salts, making it effective at removing bathroom scale, soap scum and other hard water scales
Readily biodegradable for low environmental impact

Glycolic acid is also a useful intermediate for organic synthesis, in a range of reactions including: oxidation-reduction, esterification and long chain polymerization. 
It is used as a monomer in the preparation of polyglycolic acid and other biocompatible copolymers (e.g. PLGA). 
Among other uses this compound finds employment in the textile industry as a dyeing and tanning agent, in food processing as a flavoring agent and as a preservative. 
Glycolic acid is often included into emulsion polymers, solvents and additives for ink and paint in order to improve flow properties and impart gloss.

Formal Chemical Name (IUPAC)
2-hydroxyacetic acid

Glycolic acid, 0.08% to 70%, has been nominated for inclusion on the list of bulk drug substances for use in compounding under section 503A of the Federal Food, Drug, and Cosmetic Act (FD&C Act) for topical use in the treatment of hyperpigmentation disorders and photodamaged skin 

Glycolic acid is currently available in cosmetic formulations (creams, pads, and lotions) and present as excipient in some topical drug products

Glycolic Acid Pharmacy Compounding Advisory Committee Meeting November 3, 2016 Jane Liedtka, MD Clinical Reviewer Division of Dermatology and Dental Products, Office of Drug Evaluation III 2 Glycolic Acid Review Team Jane Liedtka, MD, Clinical Reviewer, DDDP, ODE3 Ben Zhang, PhD, Chemistry Reviewer, OPQ Jianyong Wang, PhD, Pharmacology/Toxicology Reviewer, DDDP, ODE3 Doanh Tran, PhD., Clinical Pharmacology Team Leader, DCP3, OCP www.fda.gov 3 Nomination 
• Glycolic acid, 0.08% to 70%, has been nominated for inclusion on the list of bulk drug substances for use in compounding under section 503A of the Federal Food, Drug, and Cosmetic Act (FD&C Act) for topical use in the treatment of hyperpigmentation disorders and photodamaged skin www.fda.gov 4 Background
• Glycolic acid is currently available in cosmetic formulations (creams, pads, and lotions) and present as excipient in some topical drug products 
Regulatory Definitions: Drugs and Cosmetics 
• Whether a product is a cosmetic or a drug under the law is determined by a product’s intended use; different laws and regulations apply to each type of product 
• A drug is an article intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease or an article (other than food) that is intended to affect the structure or function of the body 
• A cosmetic is an article (other than soap) intended to be rubbed, poured, sprinkled, or sprayed on, introduced into, or otherwise applied to the human body for cleansing, beautifying, promoting attractiveness, or altering appearance – Regulated by CFSAN – No premarket approval of products or ingredients (except color additives) www.fda.gov 6 Cosmetic and Drug Uses of Topical Acids
• Topical Acids cause exfoliation, or shedding of the skin surface. – The extent of exfoliation depends on the type and concentration of topical acid, its pH, and the other ingredients in the product – Examples of topical acids include glycolic, lactic, citric, kojic, and trichloroacetic acid 
• Examples of intended use of acids in cosmetics – “Smoothing fine lines” – “Improving skin texture and tone” 
• Examples of intended use of acids in drugs – “Hyperpigmentation disorder” or “melasma” – “Warts” or “genital warts” 
Physical and Chemical Characterization
 • Small organic molecule 
• Highly soluble in water
 • Easily characterized with various analytical techniques 
• No stability issues reported for glycolic acid in the literature 
• Likely to be stable under ordinary storage conditions in the proposed dosage forms, such as lotions and gels www.fda.gov OH HO O 8 Physical and Chemical Characterization (2) 
• Various synthetic routes to prepare glycolic acid 
• Likely impurities include: – Formaldehyde, monochloroacetic acid (starting materials) – Residual reagents – Sodium chloride, formic acid, methoxyacetic acid (byproducts from the synthesis process) • When potential impurities listed above are controlled, the physical and chemical characteristics do not raise significant safety concerns www.fda.gov 
Physical and Chemical Characterization (3) 
• Summary – Based on the available information, there are no concerns about the physical and chemical characterization when potential impurities, such as formaldehyde, are controlled at acceptable levels: 
• well-characterized small molecule 
• Likely to be stable under ordinary storage conditions 
www.fda.gov  
Pharmacology and Toxicology 
• Pharmacology – One theory for the mechanism of action of alphahydroxy acids (AHAs) in exfoliation is: AHAs reduce calcium ion concentration in the epidermis and remove calcium ions from the cell adhesions by chelation; this causes disruption in cell adhesions, and results in desquamation – Glycolic acid can suppress melanin formation by inhibition of tyrosinase activity www.fda.gov 11 Pharmacology and Toxicology (2) 
• Safety Pharmacology – An intraperitoneal dose of 1000 mg/kg glycolic acid was a potent inhibitor of oxygen consumption and glucose metabolism in rat liver and myocardium in vivo, but did not affect brain oxygen consumption 
• Acute Toxicity – Glycolic acid in high concentrations (70% solution and pure) causes local effects that are typical of a strong acid, such as dermal and eye irritation www.fda.gov 12 Pharmacology and Toxicology (3)
 • Repeat Dose Toxicity – In a 3-week dermal toxicity study in hairless guinea pigs, erythema and/or flaking of the skin were noted at 5% and 10% concentrations of glycolic acid – Glycolic acid was a potent calculi inducer in 4- to 12-week repeat dose oral toxicity studies in rats, with an increase in renal oxalate and nephrotoxic effects – In a 2-week inhalation toxicity study in rats, respiratory tract irritation, hepatocellular degeneration and thymus atrophy were noted www.fda.gov 13 Pharmacology and Toxicology (4) 
• Genotoxicity – Glycolic acid was negative for mutagenicity in the Ames test and the Mouse Lymphoma assay – Glycolic acid was negative for clastogenicity in an in vitro chromosome aberration assay and an in vivo micronucleus assay in mice 
• Carcinogenicity – Glycolic acid did not show photocarcinogenic potential in SKH-1 hairless mice  
• Reproductive and Developmental Toxicity – Oral (gavage) doses of glycolic acid up to 600 mg/kg/day were administered to female rats during gestation days 7-21 – Maternal toxicity was seen at doses ≥ 300 mg/kg/day – Developmental toxicity was also noted at doses ≥ 300 mg/kg/day, including fetal weight reduction and increases in skeletal malformation www.fda.gov 15 Pharmacology and Toxicology (6) 
• Summary – There is lack of nonclinical data for the evaluation of chronic dermal toxicity and dermal carcinogenic potential of glycolic acid – The available nonclinical data do not raise serious safety concerns about glycolic acid when used topically at low concentrations 
• Topical application of glycolic acid enhances photo-irritation by ultraviolet light – Because of the potential to enhance sensitivity to sunburn, CFSAN guidance for industry recommends that labeling for cosmetics containing AHAs include a sunburn alert 
• Sunburn Alert: This product contains an alpha hydroxy acid (AHA) that may increase your skin’s sensitivity to the sun and particularly the possibility of sunburn. Use a sunscreen, wear protective clothing, and limit sun exposure while using this product and for a week afterwards www.fda.gov 17 Human Safety (2) 
• Pharmacokinetic data – No reports of human pharmacokinetic studies following topical application – In vitro studies indicate pH and time dependence for glycolic acid penetration of skin: ↓in pH or ↑in time of application enhanced penetration www.fda.gov 18 Human Safety (3)

Cases retrieved from CAERS 
• Clinical trials – melasma – Mainly, local irritancy manifestations such as burning, erythema, swelling and vesiculation – Rarely post-inflammatory hyperpigmentation and scarring 
• Clinical trials – photodamaged skin – Erythema, dryness • Reported adverse reactions appear to be readily manageable and temporary in duration 
• No information on long-term outcomes 
• Alternative Therapies – Melasma 
• The approved drug product, Tri-Luma, is indicated for the short-term treatment of moderate-to-severe melasma of the face in the presence of measures for sun avoidance, including the use of sunscreens – Photoaging
 • Numerous topical retinoids are approved (e.g., tretinoin and tazarotene products) as “an adjunctive agent for use in the mitigation (palliation) of fine facial wrinkles in patients who use comprehensive skin care and sunlight avoidance programs” 
• Summary – Available information does not raise major safety concerns associated with the topical use of glycolic acid  
• Clinical Trials – Hyperpigmentation – Literature search revealed multiple reports of studies involving the use of glycolic acid for the treatment of melasma and other hyperpigmentation disorders – Most were active controlled trials; there was one trial which included vehicle as control www.fda.gov 22 Effectiveness (2) 
• Clinical Trials – Photoaging – Some trials on hyperpigmentation disorders also included endpoints traditionally associated with photoaging studies – Two clinical trials specifically addressed the effect of glycolic acid on manifestations of changes associated with photoaging www.fda.gov 23 Effectiveness (3) 
• Summary of Clinical Trial Data – Melasma and Other Hyperpigmentation Disorders: 
• Glycolic acid peels of 20% to 70% 
• Improvement with glycolic acid comparable to that with other peels, such as tretinoin, trichloroacetic acid, lactic acid, Jessner solution, or capryloyl salicylic acid 
• Summary of Clinical Trial Data – Manifestations of Changes associated with Photoaging: 
• As a component in Vivite Skin Care System: similar effect on wrinkles when compared to Cetaphil 
• As 8% Cream: superior to vehicle for sallowness and overall severity of photodamage
 • Seriousness of the conditions for proposed use of glycolic acid – Hyperpigmentation disorders and photodamaged skin are not serious conditions per se, but pathological changes predisposing to skin cancer may be associated with photodamage 
• Summary – Numerous active controlled trials show consistently positive results in the treatment of melasma with glycolic acid, either as a peel or as a topical agent – Overall, the evidence suggests a role for second line treatment of melasma that failed standard therapy or as adjunctive treatment to commonly used topical medications – Some evidence from a vehicle-controlled trial may support effectiveness of glycolic acid for mitigation of manifestations of photodamaged skin www.fda.gov 27 Historical Use in Compounding 
• Glycolic acid has been used in pharmacy compounding in the U.S. since at least the mid-1990s 
• Uses of glycolic acid have included: ameliorating the appearance of skin aging, melasma and other hyperpigmentation disorders, calluses, keratoses, acne, and psoriasis 
• Extent of use cannot be determined; however, countries with reported use include Brazil, Mexico, France, Singapore, Thailand, Korea, India, Turkey 
• Foreign pharmacopeias 

•    hydroxyacetic acid
•    Hydroxyethanoic Acid
•    HOCH2COOH
•    2-Hydroxyethanoic acid
•    alpha-hydroxyacetic acid
•    2-Hydroxyacetic acid
•    Glycollic acid
•    alpha-Hydroxyacetate
•    Hydroxyacetate
•    Hydroxyethanoate
•    Sodium glycolate
•    GlyPure
•    Glycocide
•    a-Hydroxyacetate
•    Glycollate
•    a-Hydroxyacetic acid
•    Glycolate
•    2-Hydroxyacetate
•    GlyPure 70
•    alpha-Hydroxyacetic acid
•    α-hydroxyacetic acid
•    Glycolic acid
•    Hydroxyacetic Acid

Acetic acid, 2-hydroxy-
AKOS BBS-00004277
2-HYDROXYACETIC ACID
GLYCOLIC ACID, HIGH PURITY, 70 WT.% SOLU TION IN WATER
GLYCOLIC ACID REAGENTPLUS(TM) 99%
GLYCOLIC ACID SOLUTION, ~55% IN WATER
GLYCOLIC ACID, TECH., 70 WT. % SOLUTION IN WATER
GLYCOLIC ACID SIGMAULTRA
Glycolic acid solution approx. 57%
GlycolicAcid(HydroxyaceticAcid)
GlycollicAcid,67-70%SolutionInWater
GlycolicAcid70%(InWater)ForSynthesis
GlycolicAcid,70%Solution
Glycolicacid,98%
GLYCOLIC ACID FOR SYNTHESIS 250 G
GLYCOLIC ACID FOR SYNTHESIS 100 G
GLYCOLIC ACID FOR ANALYSIS EMSURE
GLYCOLIC ACID FOR SYNTHESIS 1 KG
Glycolic acid solution high purity, 70 wt. % in H2O
RARECHEM AL BO 0466
Glycolic acid, 67% in water
GLYCOLICACID,CRYSTAL,REAGENT
CHC-22
GLYCOLATE
Glykolsure
GLYCOLIC ACID: 70% AQUEOUS SOLUTION
Glycolic acid, ca 67% aq. soln.
Glycolic Acid (ca. 70% in Water, ca. 12mol/L)
Glycolic acid 70% (cosmetic garde)
Glycolic acid 70% (industrial grade)
Glycolic acid >=97.0% (T)
Glycolic acid ReagentPlus(R), 99%
Glycolic acid solution technical grade, 70 wt. % in H2O
Glycolic acid Vetec(TM) reagent grade, 98%
GLYCOLIC ACID, BIOXTRA, >=98.0%&
Glycolic acid,anhydrous, free-flowing
Glycolic acid, 70% in water
LGB-GA
Hydroxy-acetic acid in water
glycolic
glycolicacid,solution
HOCH2COOH
hydroxy-aceticaci
Kyselina glykolova
Kyselina hydroxyoctova
kyselinaglykolova
kyselinahydroxyoctova
GLYCOLATE IC STANDARD
GLYCOLLIC ACID
GLYCOLIC ACID
HYDROXYACETIC ACID
HYDROXYETHANOIC ACID
GLYCOLIC ACID 70% TECHNICAL GRADE
GLYCOLIC ACID 99%, POWDER
Glycolic Acid, 70%, High Purity
Glycolic Acid, 70%, Technical
Glycolic acid, 99% 100GR
Glycolic acid, 99% 25GR