Benzoyl peroxide, a powerful antimicrobial that also has anti-inflammatory and anti-comedogenic properties, has been used specifically as a topical acne treatment since 1934.¹ It is commonly available as a gel, cream, and lotion, though higher concentrations (>5%) in the gel were found to have an increased incidence of irritant dermatitis while smaller concentrations remained equally successful in reducing Propionibacterium acnesP. acnes.² Other forms of benzoyl peroxide for acne therapy include soaps, pads, masks, washes.(1) A new topical product combining benzoyl peroxide with a retinoid has also been recently approved by the U.S. Food and Drug Administration (FDA), and experts report that it significantly improves the efficacy of retinoid treatment.^1,3

Results of randomized clinical trials suggest that when combined with topical antibiotics, benzoyl peroxide may be more effective than when either agent is used alone. In severe cases of acne where oral systemic antibiotics (e.g., erythromycin, clindamycin, and tetracycline) are necessary, it contributes significantly to suppressing antibiotic-resistant strains of P. acnes and other opportunistic bacteria.¹ In fact, there has never been a report of bacteria developing a resistance to benzoyl peroxide, which is why it is often used in conjunction with both oral and topical antibiotics.³