Topical antibacterial therapy for acne vulgaris.

Topical antibiotics and benzoyl peroxide, are the two main topical antibacterial treatments indicated for mild-to-moderate acne vulgaris. Topical antibiotics act both as antibacterial agents suppressing Propionibacterium acnes in the sebaceous follicle and as anti-inflammatory agents. Benzoyl peroxide is a powerful antimicrobial agent that rapidly destroys both bacterial organisms and yeasts. Topical clindamycin and erythromycin have been proven to be effective against inflammatory acne vulgaris in concentrations of 1-4% with or without the addition of zinc. However, none of the antibacterials tested was more effective than benzoyl peroxide, which also has the advantage of not being associated with antimicrobial resistance. Topical antibacterial therapy should be discontinued once improvement is observed. If no improvement is observed within 6-8 weeks, the agent should be discontinued and a therapeutic switch considered. The primary limitation of benzoyl peroxide for some acne vulgaris patients is cutaneous irritation or dryness.Antibacterial therapy can be used in combination with other agents. Combining topical antibiotics and topical retinoids may enhance the efficacy, since the retinoid will improve the penetration of the antibiotic. Combining a topical antibiotic with benzoyl peroxide may increase the bactericidal effect of the antibiotic and reduce the potential for bacterial resistance. Topical and oral antibacterials should not be used in combination for the treatment of acne vulgaris, since this association may increase the risk of bacterial resistance.