The role of benzoyl peroxide in the new treatment paradigm for acne.

Bacterial resistance became a true clinical concern for dermatologists in the 1980s, when the first reports emerged of the resistance of <i>Propionibacterium acnes</i> to oral antibiotics. Subsequent studies have documented acne treatment failure associated with resistance to topical antibiotics. Beyond dermatology practice, antibiotic resistance has now become recognized as a worldwide health concern. In contrast to antibiotics commonly used in the treatment of acne, benzoyl peroxide (BP)'s mechanism of action is different. Benzoyl peroxide is a bactericidal agent. Combining BP with a topical antibiotic in a stable formulation has been proven in clinical trials to reduce total P acnes count by 99.7% after 1 week of therapy, eliminating both susceptible and resistant strains of P acnes. However, we have recently noticed BP's benefits as monotherapy in the treatment of acne. Benzoyl peroxide works rapidly on P acnes without causing antibiotic resistance. Hence, we may have to reconsider the role of topical antibiotics such as clindamycin in the treatment paradigm of acne vulgaris.