Considered the most effective over-the-counter choice for a topical antibacterial agent in the treatment of acne. 
The amount of research demonstrating the effectiveness of benzoyl peroxide is exhaustive and conclusive. [1,2,3] Among benzoyl peroxide’s attributes is its ability to penetrate into the hair follicle to reach the bacteria that cause the problem, and then kill them—with a low risk of irritation. It also doesn’t pose the problem of bacterial resistance that some prescription topical antibacterials (antibiotics) do. 
Research has also shown that benzoyl peroxide is more effective than some other prescription treatments for acne, such as oral antibiotics and topical antibiotics. [1,2,3]
Benzoyl peroxide solutions range in strength from 2.5% to 10%. It is best to start with lower concentrations because a 2.5% benzoyl peroxide product is much less irritating than a 5% or 10% concentration, and it can be just as effective. [1,2,3]
Although once thought to be a problem if applied at the same time as products with retinol or prescription retinoids (such as Renova, Retin-A, Differin, Tazorac, and generic tretinoin), recent research has shown that not to be the case. 
- Bowe W, Shalita A. Effective Over-the-Counter Acne Treatments. Semin Cutan Med Surg. 2008;27(3):170-176.
- Sagransky M, Yentzer B, Feldman S. Benzoyl peroxide: a review of its current use in the treatment of acne vulgaris. Expert Opin Pharmacother. 2009;10(15):2555-62.
- Simonart T. Newer approaches to the treatment of acne vulgaris. Am J Clin Dermatol.. 2012;13(6):357-64.
- Bowe W. Antibiotic Resistance and Acne: Where We Stand and What the Future Holds.. J Drugs Dermatol.. 2014;13(6):S66-S70.
- Del Rosso J, Pillai R, Moore R. Absence of Degradation of Tretinoin When Benzoyl Peroxide is Combined with an Optimized Formulation of Tretinoin Gel (0.05%). J Clin Aesthet Dermatol. 2010;3(10):26-28.