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Benzoyl Peroxide
Benzoyl Peroxide
Kills the bacteria behind breakouts. Found in spot gels and washes; 2.5% works about as well as 10%, with less irritation.
What it does
It releases oxygen that kills the bacteria involved in red, swollen breakouts. 2.5% works about as well as 10%, with less irritation. It’s sold over the counter, often as a spot gel or wash.
The evidence, graded
strongFor a first benzoyl peroxide (BPO) product, 2.5% is the place to start. Stores sell 2.5% to 10%. In double-blind trials, 2.5% cleared pimples about as well as 5% and 10%, with less peeling, redness and burning than 10%. Stronger products can cause more dryness and flaking. A BPO wash counts too. BPO bleaches towels, sheets and clothes, so let it dry or rinse it off.AAD 2023 · AAD patient guidance ↗
expert consensusTopical benzoyl peroxide at 5% or below is generally considered safe across all trimesters of pregnancy and during breastfeeding. Some clinicians still prefer caution — talk to your OB or dermatologist before starting.Bozzo 2011 · Canadian Family Physician ↗
expert consensusDermatologists pair a topical antibiotic, such as clindamycin, with benzoyl peroxide. The AAD says that when a topical antibiotic is part of your plan, you use it along with an acne medication or wash that contains benzoyl peroxide, and that this reduces your risk of antibiotic resistance. Some prescription products combine the two, for example 5% benzoyl peroxide with 1% clindamycin.AAD 2024 · AAD patient guidance ↗
emergingFine in one routine if split — benzoyl peroxide in the morning, retinol at night. In a lab test, mixing tretinoin with benzoyl peroxide and leaving the mixture in light destroyed more than half the tretinoin in about two hours and 95% of it in a day. Nobody ran that test on retinol, and nothing was applied to skin; splitting them costs nothing and protects the dose.Martin 1998 · British Journal of Dermatology ↗
emergingFine in one routine if split — benzoyl peroxide in the morning, tretinoin at night. Mixed with benzoyl peroxide and left in light, tretinoin lost more than half its strength in about two hours and 95% in a day. That was a lab mixture, not skin. A product that contains both is used as its label says.Martin 1998 · British Journal of Dermatology ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Also known as
BPO
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