Benzoyl peroxide was found to be effective in treating mild acne over 80 years ago and has been an important component of acne treatment since.
Benzoyl peroxide is the active ingredient in many of the most common non-prescription acne medicines, such as Clearasil®, PanOxyl®, Proactiv®, and Stridex®. It is also the active ingredient some prescription-strength medications, such as Acanya® Gel and Benzac®.
Benzoyl peroxide may also be formulated with other acne medications to create a combination product. For instance, Epiduo® combines benzoyl peroxide with adapalene, a topical retinoid. Benzoyl peroxide works by removing dead skin cells that can clog the pores and acting as an antibacterial agent that reduces the P. acnes bacteria on the skin.
Benzoyl peroxide is available in a variety of concentrations ranging from 2.5% to 10%. Research suggests that 5% and 10% concentrations are not significantly more effective than lower concentrations, and that lower concentration may be better tolerated.
Benzoyl peroxide commonly causes dry and irritated skin, but these side effects often lessen after use for a week or two. Generally people with dry or sensitive skin may wish to start with the lower concentration and build up the concentration over time as tolerance develops.
Benzoyl peroxide can bleach hair, sheets, towels and clothing so delicate clothing should not be worn after applying benzoyl peroxide on the back or chest (truncal acne).
Benzoyl peroxide may be recommended for use even after acne clears to prevent new acne lesions from forming.