Benzoyl peroxide for acne – how it works

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Acne – a chronic inflammatory skin disorder – is known to be caused by a combination of factors, including abnormal desquamation of the follicular epithelium, excessive sebum production, inflammation and the presence of the bacterium Propionibacterium acnes. Benzoyl peroxide is commonly used to treat acne; it works as an antiseptic to reduce the amount of bacteria on the skin. It is most commonly used in the form of a gel or face wash at a concentration of around 5%.

benzoyl peroxide

How benzoyl peroxide works

Benzoyl peroxide works on several levels to treat acne: benzoyl peroxide has bactericidal, keratolytic and mildly anti-inflammatory properties. The antibacterial activity of benzoyl peroxide is due to the formation of reactive oxygen species, these radicals subsequently react with bacterial proteins causing death.

Benzoyl peroxide also shows similar keratolytic activity to salicylic acid – it is thought to be due to radical-induced damage, loosening intercellular connections between keratinocytes, helping them to shed. 

The reactive oxygen species that form from benzoyl peroxide are also thought to reduce inflammation through reducing bacterial levels and also through damaging immune cells found in inflammatory lesions.

In addition, due the broad mode of action of benzoyl peroxide, it is also insusceptible to bacterial resistance.

Top tips

  • Use 1-2 times a day.
  • Benzoyl peroxide 5% gel or wash takes around 4 weeks to start working so stick with it.
  • Skin irritation can occur so build up tolerance slowly.
  • It is possible for benzoyl peroxide to bleach hair and clothes so try to keep it away from them.
  • Sunscreen usage is important when using benzoyl peroxide due to increased skin photosensitivity.

Top picks

Differin Acne Face Wash with Benzoyl Peroxide

The makers of Differin Gel have developed an acne face wash containing 5% benzoyl peroxide. It is developed by dermatologists who have got the formula just right – using a lower concentration of benzoyl peroxide so to avoid irritation but packs the same punch as higher concentration-containing products.

Neutrogena 10% benzoyl peroxide gel

After a budget-friendly option in the form of a gel? This Neutrogena product might be the perfect choice – clinically proven to rapidly reduce the size and redness of stubborn acne in just 2 hours.

111MedCo 10% Benzoyl Peroxide Acne Soap Bar

Struggling with back acne? Looking for a product you can also use on your body? This bar of soap formulated with benzoyl peroxide should do the trick.

CeraVe Acne Foaming Cream Cleanser

This fragrance free CeraVe cleanser contains 4% benzoyl peroxide as well as hyaluronic acid and niacinamide.


Cove, J. H., & Holland, K. T. (1983). The effect of benzoyl peroxide on cutaneous micro-organisms in vitro. The Journal of applied bacteriology54(3), 379–382.

Kim, M. R., & Kerrouche, N. (2018). Combination of benzoyl peroxide 5% gel with liquid cleanser and moisturizer SPF 30 in acne treatment results in high levels of subject satisfaction, good adherence and favorable tolerability. Journal of Dermatological Treatment29(1), 49-54.

Nacht, S., Yeung, D., Beasley, J. N., Jr, Anjo, M. D., & Maibach, H. I. (1981). Benzoyl peroxide: percutaneous penetration and metabolic disposition. Journal of the American Academy of Dermatology4(1), 31–37.

Brammann, C., & Müller-Goymann, C. C. (2020). An update on formulation strategies of benzoyl peroxide in efficient acne therapy with special focus on minimizing undesired effects. International journal of pharmaceutics578, 119074.