What is BHA?

Posted on by Ersin Koseoglu

Beta Hydroxy Acids - BHAs

Salicylic Acid is the only member of the BHA family. It is obtained from willow bark (willow bark), wintergreen ( wintergreen), sweet birch (sweet birch). Since the hydroxyl group is attached to the beta position of the aromatic carboxylic acid radical, it is called beta hydroxyacid [1].


Salicylic Acid is BHA used in cosmetic formulations. BHA (Salicylic Acid) ratios in products formulated for home use vary between 0.5-2%. According to the regulations, the maximum Salicylic Acid (BHA) rate that can be used in cosmetic products is 2%.

On the other hand, in clinics and skin care centers, BHA rates are between 20-30% or 50% in applications made as chemical peeling for the purpose of removing stains. The function of high-rate BHAs in the range of 20-50% applied by dermatologists in clinics is similar to AHAs. The task of BHAs at these rates is spot treatment. The most important features that distinguish BHAs from AHAs are their anti-inflammatory properties.

Due to the anti-inflammatory effects of BHAs, products containing Salicylic acid are ideal for people with unbalanced oily skin, acne and Rosacea concerns. BHAs can be used alone or in combination with other drugs used in the treatment of acne to help get rid of comedones and inflamed red acne structures faster.

BHAs are lipophilic, that is, they are fat-soluble actives. Thanks to these properties, BHAs reach the sebum production centers in the hair root and exfoliate the inside of the pores. Because of these properties, BHAs have comedolytic (acne prevention) effects [2, 3].

The comedolytic (acne prevention) properties of BHAs were studied by Klingman. In the study, microcomedones were treated with exfoliants containing 2% Salicylic Acid and 8% Glycolic Acid. According to the results of the study, a decrease was observed in microcomedones treated with BHA (salicylic acid) [4]. As a result, Salicyl Acid is effective on comedones due to its fat-soluble structure and strong comedolytic (acne prevention) effect compared to glycolic acid. It is also accepted by many scientists that Salicyl acid helps trigger collagen production due to its exfoliant effects.


  1. Leslie Baumann, Cosmetic Dermatology: Principles and Practice, Second Edition, 2008, p 150.
  2. Ahn HH, Kim IH. Whitening effect of salicylic acid peels in Asian patients. Dermatol Surg. 2006;32:372.
  3. Davies M, Marks R. Studies on the effect of salicylic acid on normal skin. Br J Dermatol. 1976;95:187
  4. Kligman A. A comparative evaluation of a novel low-strength salicylic acid cream and glycolic acid. Products on human skin. Cosmet Dermatol. 1997; 10(suppl):11S.