Beta-Hydroxy Acids (BHAs)

The most frequently used beta-hydroxy acid is salicylic acid. It is found in most over-the-counter (OTC) products and has been used primarily in the treatment of acne. Part of its effectiveness as an acne treatment may stem from its lipid solubility and ability to penetrate sebum [58].More recently, salicylic acid has been used in the treatment of photoaging with in-office peels of 20–30%. These can be quite helpful in patients who are unable to tolerate alpha-hydroxy acids since irritancy levels tend to be less with salicylic acid. In addition, it can be quite useful to combine or alternate both AHAs and BHAs since their mechanisms of action differ, and using both may be quite beneficial.