Benzoyl Peroxide & Acne
Benzoyl peroxide (aka BPO or BP) has been used in the treatment of acne since the 1930s.[2, 3] It is a potent oxidizing agent, with a propensity to bleach clothing and hair.[2, 3] Benzoyl peroxide is available in a variety of over-the-counter acne products in concentrations up to 10%.[5]
Benzoyl peroxide is considered to have antibacterial and keratolytic (inhibits buildup of keratin that can clog sebaceous follicles/pores) effects.[1] Overall, benzoyl peroxide's strength is as an antibacterial agent.[4] Its antibacterial effects are believed to be the result of numerous factors, including the release of oxygen and free-radicals.[1, 3] The release of oxygen is particularly important because propionibacterium acnes (P.acnes), the bacteria most often associated with acne, are generally considered to be anaerobic (adverse to oxygen)[10]
Benzoyl peroxide is more effective against P.acnes than any topically applied, prescription antibiotic.[6] Its efficacy in suppressing bacteria is evident from the speed at which it does so (immediately) and the fact that bacteria levels are reduced for as long as 48 hours after benzoyl peroxide is applied.[9] Unlike with antibiotics, there is no known bacterial resistence to benzoyl peroxide.[4]
Compared to its antibacterial effects, benzoyl peroxide's keratolytic and antiflammatory effects are relatively minor.[4] Benzoyl peroxide's keratolytic action results when, upon coming into contact with the skin, it creates benzoic acid, which is believed to disrupt the mechanism by which keratin cells bond together.[2]
While benzoyl peroxide is sometimes claimed to affect sebum (oil) production, it does not actually do so.[5]
When compared to salicylic acid, both treatments containing 2.5% benzoyl peroxide and 0.5% salicylic acid have roughly equivalent effects against inflammatory acne, with the salicylic acid treatment having fewer negative side effects.[7] However, benzoyl peroxide demonstrates greater effectiveness than salicylic acid against non-inflammatory acne.[7]
Benzoyl peroxide has been studied at varying concentrations, with 2.5%, 5%, and 10% having similar levels of effectiveness.[8] The lower 2.5% concentration, while similarly effective, has fewer negative side effects.[8] For a topical acne treatment, benzoyl peroxide generally provides positive results relatively quickly, with some effects typically noticable in 1-2 weeks and further improvement after 4-8 weeks.[3]
References:- Burkhart CG, Burkhart CN. Antibacterial properties of benzoyl peroxide in aerobic and anaerobic conditions. International Journal of Dermatology. 2006;45:1373-74.
- Fanta D, Bardach H, Poitscheck, C. Investigations on the Bacteriostatic Effect of Benzoyl Peroxide. Arch Derm Res. 1979;264:368-71.
- Worret, W, Fluhr, J. Acne therapy with topical benzoyl peroxide, antibiotics and azelaic acid. JDDG. 2006;4:296-99
- Gollnick H, Krautheim A. Topical Drug Treatment in Acne:Current Status and Future Aspects. Dermatology. 2003;206:29-36.
- Gollnick H, Schramm M. Topical Drug Treatment in Acne. Dermatology. 1998;196:119-125.
- Dreno B. Topical Antibacterial Therapy for Acne Vulgaris. Drugs. 2004;64(21):2389-97.
- Christine JC, Arambula K, Chon S, Kimball A. A Double-Blind Comparison of the Efficacy of a Salicylic Acid Based Acne Treatment Versus a Benzoyl Peroxide Based Acne Treatment Regimen for the Treatment of Acne Vulgaris.
- Mills OH, Kligman AM, Pochi P, Comite H. Comparing 2.5%, 5%, adn 10% Benzoyl Peroxide on Inflammatory Acne Vulgaris. International Journal of Dermatology. 1986;25(10):664-67.
- Kligman AM, Leyden JJ, Stewart R. New Uses for Benzoyl Peroxide: A Broad-spectrum Antimicrobial Agent. Internation Journal of Dermatology. 1977;16(5):413-17.
- Fluhr JW, Barson O, Gehring W, Gloor M. Antibacterial Efficacy of Benzoyl Peroxide in Phospholipid Liposomes. Dermatoloogy. 1999;198:273-77.