Keratolytic Treatments for Acne: A Review

By: Ali Alikhan, MD, Mayo Clinic; and Howard I Maibach, MD, University of California School of Medicine

Posted: September 29, 2010, from the October 2010 issue of Cosmetics & Toiletries.

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Glycolic acid, a naturally occurring organic acid (α-hydroxy acid), is a component in many cosmetic formulations. Glycolic acid chemical peels may serve as valuable adjuvant therapy in acne. Comedones are removed after only two or three peels, and the procedure may be repeated every two or three weeks. Between peels, low concentrations of glycolic acid may be used as a daily cleanser to prevent re-occlusion of follicles.

A randomized split-face prospective clinical trial comparing glycolic acid to Jessner’s solution (see Jessner’s Solution) demonstrated significant acne improvement in both treatments after three applications. However, glycolic acid produced significantly less exfoliation than Jessner’s solution, suggesting superior tolerability.²⁴ In a similar study comparing glycolic acid with salicylic acid peels, both were equally effective by the second treatment; however, salicylic acid demonstrated greater sustained effectiveness and more favorable tolerability.²⁵ A study examining 35% and 50% glycolic acid peels on Asian patients found significant resolution of comedones, papules and pustules; decreased follicular pore size; improvement in acne scars; and favorable tolerability.²⁶

Conclusion

Taken together, a century of clinical trials and clinical use support the efficacy of keratolytics in acne. While many keratolytics are available by prescription only, OTC keratolytics offer treatment to acne sufferers without a dermatologist. This author suspects that some prescription keratolytic agents will eventually be available in the OTC market should their toxicity profile indicate safety in OTC usage. Therefore, OTC acne formulators should familiarize themselves with all keratolytics, both prescription and OTC.

OTC keratolytics, the most enduring being SA and BPO, have a remarkable safety ratio. It remains to be seen whether some of the newer prescription keratolytic agents will prove to have an equivalent or nearly equivalent safety profile. There unfortunately are no illustrative comparisons between the various keratolytic agents (OTC and prescription) to help acne sufferers choose the most effective treatment for them, particularly for those with mild to moderate acne. With novel in vivo and in vitro keratolytic assays, the formulator finally has the opportunity to obtain efficacy data in as short as a one-day dosing.²⁷ This presents opportunities for refinement and improvement of keratolytic agents. Reproduction of the article without expressed consent is strictly prohibited.

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Send e-mail to alialikhan1@yahoo.com.
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