J Drugs Dermatol. 2009 Jul; 8(7): 657-61Fakhouri T, Yentzer BA, Feldman SRBACKGROUND: Antibiotic resistance of Propionibacterium acnes (P. acnes) is a growing phenomenon in the wake of widespread use of topical and systemic antibiotics for acne vulgaris. Benzoyl peroxide has a proven track record of safety and efficacy, and can decrease reliance on antibiotics in the treatment of acne. PURPOSE: To review the literature for methods to increase the efficacy and tolerability of benzoyl peroxide (BPO). METHODS: A PubMed literature search was done using the terms "benzoyl peroxide," "vehicle," "mechanism," and "delivery system." Relevant papers were reviewed for methods of increasing BPO efficacy and tolerability. RESULTS: BPO in concentrations of 2.5%, 5% and 10% are equally effective at treating inflammatory acne. However, higher concentrations are associated with more adverse effects. The efficacy of BPO may be enhanced by the presence of Vitamin E and tertiary amines. BPO is also more efficacious if used in combination with topical retinoids than as a monotherapy. Novel vehicles including a microparticle delivery system and those with a hydrophase or urea base increase the tolerability of BPO without sacrificing efficacy. CONCLUSION: Benzoyl peroxide has a proven track record of safety and efficacy for the treatment of acne. Recent discoveries have provided new methods of increasing the efficacy and tolerability of topical BPO, making it useful as monotherapy for mild acne or as an adjunct in the treatment of moderate to severe acne vulgaris.