Discuss the topical therapy of acne vulgaris.

The single most important topical medications used to treat acne are retinoids. We now have numerous topical preparations to choose from that are less irritating and decrease the most common complaint associated with class of acne therapy. These include adapalene (Differin), tazarotene (Tazorac), and tretinoin (Avita, Retin-A, Retin-A Micro). Twelve weeks of use is required for maximum benefit. Retinoids are the only drugs that normalize keratinization within the follicular infundibulum and prevent comodone formation. Propironibacterium acnes, the anaerobic bacterium associated with acne pathogenesis, stimulates the innate immune response via Toll-like receptors (TLRs). This sets off an inflammatory cascade of cytokines. Retinoids are known to downregulate TLRs and inhibit downstream inflammatory transcription factors. Recent recommendations from a global alliance to improve outcomes in acne recommended that retinoid-based combination therapy (retinoid plus antimicrobial or benzoyl peroxide) be the first-line treatment for most forms of acne vulgaris. Retinoids have been shown to maintain improvement achieved with this initial combination therapy.


Other topical treatments include benzoyl peroxide (BPo), topical antibiotics (erythromycin, clindamycin, and sodium sulfacetamide), a-hydroxy acids, salicylic acid, and azelaic acid. Antibiotic resistance of P. acnes has become more common. More than half of patients undergoing therapy with a topical antibiotic will develop resistance. No bacterial resistance has been reported with topical benzoyl peroxide. The following are recommendations for preventing bacterial resistance in the treatment of acne: combining antimicrobials with a retinoid and BPo, limiting the duration of antimicrobial therapy, not using antimicrobials as monotherapy, and avoiding concurrent use of oral and topical antibiotics, especially if chemically different.

Theboutot D, Gollnick, H, Bettoli V, et al: New insights into the management of acne: an update from the Global Alliance to Improve Outcomes in Acne Group, J Am Acad Dermatol 60:S1–S50, 2009.