Benzoyl Peroxide is the work horse for inflamed acne. If used properly by starting with lower strengths and and timing it use, you can kiss inflamed acne good bye! But remember, all BPO is NOT created equal. Over the counter and prescription BPO and be full of pore clogging ingredients and severely irritate the skin. See an Acne Specialist for the best BPO available.



Benzoyl peroxide kills bacteria by reacting with bacterial membranes (via oxidation and free radical mechanisms). The beauty of benzoyl peroxide compared to traditional antibiotics is that bacteriacan’t become resistant, and it actually works more effectively than antibiotic creams too! BPO is often combined with other acne treatments for these reasons.


Benzoyl peroxide dissolves well in oil (it’s lipophilic), which means it can penetrate deep into pores and pimples.


You don’t often see it listed as an exfoliant, but benzoyl peroxide is actually fantastic at loosening skin cells deep in the outer layer of skin (stratum corneum), deeper than salicylic acid can reach.


Benzoyl peroxide also reduces inflammation, an important contributor to the development of a proper breakout.

Downsides Of Benzoyl Peroxide

Irritation: Because it’s an oxidant and produces free radicals, benzoyl peroxide decreases the levels of antioxidant vitamin E in the top layers of skin. This often leads to dryness, redness, peeling and stinging, especially at higher concentrations and in formulations with lots of alcohol. Luckily, 2.5% benzoyl peroxide is as effective as higher concentrations, and causes less irritation. Make sure you moisturize while using BPO!

Bleaching: Peroxides are good at bleaching, and benzoyl peroxide does its chemical family proud by staining your clothes, pillowcases, towels and possibly even your hair white. The solution is to only use white linen when you have benzoyl peroxide on your face and fingers, and to keep your hair off your face.

Allergy (rare): Less than 2% of people are allergic to benzoyl peroxide.

Interaction with tretinoin: Benzoyl peroxide inactivates tretinoin (Retin-A), but the two work well in combination to fight acne. If you want to use the two ingredients together, you can either use BPO in the morning and tretinoin at night, or on alternating days, or use a product that’s specially formulated to keep the tretinoin stable (e.g. Retin-A Micro, which uses microspheres). You could also use a different retinoid, such as adapalene or tazarotene, which don’t interact with BPO.


The best way to use benzoyl peroxide is to cover your clean face with a thin layer of 2.5% or 5% benzoyl peroxide gel, 1-3 times a day. Follow with moisturizer, and use sunscreen during the day.