salicylic acid, how it helps

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What is Salicylic Acid?

Salicylic Acid is a beta hydroxy acid derived from the bark of the willow tree. Beta hydroxy acids have a larger molecule than their cousin, alpha hydroxy acids. The larger molecule size keeps the beta hydroxy acid on the surface of the skin allowing it to more effectively penetrate and exfoliate within the pore. This action within the pores make it an ideal exfoliant for use on acne and acne-prone skin.

The larger molecule size of salicylic acid produces less irritation than alpha hydroxy acids, making it a welcome alternative for those with sensitive skin.

Who Should Use Salicylic Acid?

Salicylic Acid is best on acne-prone and sensitive skin types. The pore-cleansing properties of salicylic acid make it a more effective comedone fighter. Those with sensitive skin who cannot tolerate alpha hydroxy acids may find that they are able to use salicylic acid with good results. However, alpha hydroxy acid's penetration into the deeper layers of the skin produce better anti-wrinkle and anti-aging benefits.
Look for concentrations of 1-2% in any salicylic acid product to assure on effective concentration. A 1% concentration would be better or sensitive skin types and a 2% concentration would be useful on stubborn acne.

Can Salicylic Acid Be Combined With Other Therapies?

As an exfoliant, salicylic acid can actually increase the benefits of other therapies used in conjunction with it. However, care should be taken to watch for signs of excess irritation. If irritation occurs, then it would not be a good idea to continue combining therapies. For acne prone skin, retinol makes a good adjunct therapy for salicylic acid.

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Salicylic acid.
Referred to as beta hydroxy acid (BHA), it is a multifunctional ingredient that addresses many of the systemic causes of blemishes (Source: Seminars in Dermatology, December 1990, pages 305–308). For decades dermatologists have been prescribing salicylic acid as an exceedingly effective keratolytic (exfoliant), but it also is an anti-irritant This is because salicylic acid is a derivative of aspirin (both are salicylates—aspirin’s technical name is acetyl salicylic acid), and so it also functions as an anti-inflammatory. (Sources: Archives of Internal Medicine, July 2002, pages 1531–1532; Annals of Dermatology and Venereology, January 2002, pages 137–142; Archives of Dermatology, November 2000, pages 1390–1395; and Pain, January 1996, pages 71–82). Another notable aspect of salicylic acid for treating breakouts is that it has antimicrobial properties (Source: Preservatives for Cosmetics, 1996, by David Steinberg, Allured Publishing; and Health Canada Monograph Category IV, Antiseptic Cleansers, at www.hc-sc.gc.ca/english/). It is also well documented that it can improve skin thickness, barrier functions, and collagen production (Sources: Dermatology, 1999, volume 199, number 1, pages 50–53; and Toxicology and Applied Pharmacology, Volume 175, Issue 1, pages 76–82). As an exfoliant, in concentrations of 8% to 12%, it is effective in wart-remover medications. In concentrations of 0.5% to 2%, it is far more gentle, and, much like AHAs (See AHAs), can exfoliate the surface of skin. In addition, BHA has the ability to penetrate into the pore (AHAs do not), and thus can exfoliate inside the pore as well on the surface of the skin; that makes it effective for reducing blemishes, including blackheads and whiteheads.


Treating Skin With Beta Hydroxy Acid - Salicylic Acid
With increasing research into what causes wrinkles and the effects of photoaging, the use of hydroxy acids has increased greatly in popularity. There are two types of hydroxy acids - alpha and beta. Alpha hydroxy acids are exfoliants derived from fruit and milk sugars such as glycolic acid produced from sugar cane and lactic acid produced from milk. There is only one beta hydroxy acid - salicylic acid.

How Beta Hydroxy Acid Works
Beta hydroxy acid works mainly as an exfoliant. It causes the cells of the epidermis to become "unglued" allowing the dead skin cells to slough off, making room for regrowth of new skin.

Between Alpha and Beta Hydroxy Acids
The main difference between alpha hydroxy acids and beta hydroxy acid is their lipid (oil) solubility. Alpha hydroxy acids are water soluble only, while beta hydroxy acid is lipid (oil) soluble. This means that beta hydroxy acid is able to penetrate into the pore which contains sebum and exfoliate the dead skin cells that are built up inside the pore. Because of this difference in properties, beta hydroxy acid is better used on oily skin with blackheads and whiteheads. Alpha hydroxy acids are better used on thickened, sun-damaged skin where breakouts are not a problem.

Beta Hydroxy Acid and Irritation
Beta hydroxy acid appears to be less irritating than alpha hydroxy acid even though it penetrates deeper into the pore. This occurs because salicylic acid is derived from acetylsalicylic acid, or aspirin. Aspirin has anti-inflammatory properties, and salicylic acid retains many of these anti-inflammatory properties. Despite this fact, beta hydroxy acid can still cause skin irritation. Symptoms of irritation include redness, burning, itching, pain, and possibly scarring. People with darker colored skin are at a higher risk of scarring pigment changes with beta hydroxy acid.

Using a Beta Hydroxy Acid
Beta hydroxy acid is found in a variety of skin care products including moisturizers, cleansers, eye cream, sunscreen, and foundations. Here are some guidelines to use when trying to decide which hydroxy acid formulation to use:

It is best to pick one product that contains the proper formulation of beta hydroxy acid to use as your exfoliant, and then choose other skin care products or cosmetics that don't contain hydroxy acids to reduce the likelihood of skin irritation.
Using beta hydroxy acid in a moisturizer base may be the best combination of products.
Cleansers containing beta hydroxy acid are not very effective because the beta hydroxy acid must be absorbed in the skin to work. Cleansers are washed off before this absorption occurs.
At this time there are no effective products that combine beta hydroxy acid and sunscreen, because sunscreen is not stable at the pH required to make the beta hydroxy acid effective.
Sunscreen MUST be applied liberally when using an alpha hydroxy acid product. The sunscreen should have an SPF of at least 15 for UVB protection and contain avobenzone, titanium dioxide, or zinc oxide for UVA protection.
Beta hydroxy acid works best in a concentration of 1% to 2% and at a pH of 3 to 4.
Unfortunately, cosmetic manufacturers are not required to pH information on the label. The only way to know for sure the pH of a product is to test with a pH strip. Paula Begoun has done this in her skin care product reviews found in her book "Don't go to the Cosmetics Counter Without Me."
Unlike alpha hydroxy acid that must be listed in the top 3 ingredients to indicate the appropriate concentration, beta hydroxy acid can be listed in the middle or even towards the bottom of the ingredient list because it is effective at lower concentrations.

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Beta Hydroxy Acids in Cosmetics
article syndicated from FDA

Throughout the last decade, alpha hydroxy acids (AHAs) have increasingly appeared as ingredients in cosmetics intended to reduce the signs of aging in the skin. More recently, beta hydroxy acids (BHAs), or a combination of AHAs and BHAs, have appeared as ingredients in these skin care products. While both AHAs and BHAs act as exfoliants, it has been claimed that BHAs are effective in reducing the appearance of fine lines and wrinkles, and improving overall skin texture, without the occasional irritation associated with the use of AHAs.

BHA ingredients may be listed as -

salicylic acid (or related substances, such as salicylate, sodium salicylate, and willow extract) *
beta hydroxybutanoic acid
tropic acid
trethocanic acid
Currently, the BHA most commonly used in cosmetics is salicylic acid. On rare occasions, citric acid is also cited as a BHA in cosmetic formulations. More commonly, citric acid is referred to as an AHA.

The safety of salicylic acid used as a cosmetic ingredient has been evaluated by both the cosmetic industry and FDA. At a meeting in February 2000, the Cosmetic Ingredient Review (CIR) Expert Panel, the cosmetic industry's independent body for reviewing the safety of cosmetic ingredients, reached the tentative conclusion that the use of salicylic acid related substances in cosmetics is "safe as used when formulated to avoid irritation and when formulated to avoid increased sun sensitivity." CIR added that "when sun sensitivity would be expected, directions for use [should] include the daily use of sun protection."

In other words, according to CIR Director Alan Andersen, products containing salicylic acid should either contain a sunscreen or bear directions advising consumers to use other sun protection. In order to comply with the CIR recommendations, cosmetic manufacturers should test their products to determine whether or not they cause an increase in sensitivity to the harmful ultraviolet radiation in sunlight.

The long-term safety of salicylic acid in cosmetics also is being evaluated in studies initiated by FDA and sponsored by the National Toxicology Program. These government-sponsored studies are examining the long-term effects of both glycolic acid (an AHA) and salicylic acid on the skin's response to ultraviolet (UV) light. These studies have determined that applying glycolic acid to the skin can make people more susceptible to the damaging effects of the sun, including sunburn.

Until these safety assessments are completed, FDA advises that similar precautions be taken for the use of cosmetics containing AHAs and BHAs. These precautions are:

Test any product that contains a BHA on a small area of skin before applying it to a large area. If you use cosmetics with BHAs and experience skin irritation or prolonged stinging, stop using the product and consult your physician.
Follow the use instructions on the label. Do not exceed the recommended applications.
Avoid using BHA-containing products on infants and children.
Use sun protection if you use a BHA product.
Consumers should report any adverse reactions, such as irritation or sun sensitivity, associated with the use of BHAs to their local FDA office, listed in the Blue Pages of the phone book, or to FDA's Office of Consumer Affairs at 1-800-532-4440.

If you have purchased a product whose outer packaging has become separated from the product and you are unsure whether it contains BHAs, call the manufacturer, whose phone number may be listed on the inner packaging.

*From a chemist's perspective, salicylic acid is not a true BHA. However, cosmetic companies often refer to it as a BHA and, consequently, many consumers think of it as one.

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Ingredient Terms

Here are some ingredient terms that indicate a cosmetic contains alpha or beta hydroxy acids.


Alpha hydroxy acids:

glycolic acid

lactic acid

glycolic acid + ammonium glycolate

alpha-hydroxyethanoic acid + ammonium alpha-hydroxyethanoate

alpha-hydroxyoctanoic acid

alpha-hydroxycaprylic acid

hydroxycaprylic acid

mixed fruit acid

triple fruit acid

tri-alpha hydroxy fruit acids

sugar cane extract

alpha hydroxy and botanical complex

L-alpha hydroxy acid

glycomer in crosslinked fatty acids alpha nutrium


Beta hydroxy acids:

salicylic acid **

beta hydroxybutanoic acid

tropic acid

trethocanic acid


Alpha and beta hydroxy acids:

malic acid

citric acid


** From a chemist's perspective, salicylic acid is not a true BHA. However, cosmetic companies often refer to it as a BHA and, consequently, many consumers think of it as one.