Benzoyl Peroxide
Kills acne bacteria directly, and unlike antibiotics they cannot become resistant to it.
Benzoyl peroxide releases oxygen into the pore, which the bacteria involved in acne cannot survive. That mechanism is why resistance never develops, and why it is often paired with topical antibiotics. It bleaches fabric readily — pillowcases and towels included — and it is drying, so lower strengths used consistently usually beat higher ones used sporadically.
2.5% works about as well as 10% with far less irritation. Use white towels.
Benzoyl peroxide oxidises most retinoids on contact, and both are drying.
Benzoyl peroxide in the morning, retinoid at night. Adapalene is the exception — it is stable alongside benzoyl peroxide.
Benzoyl peroxide oxidises vitamin C, wasting both.
Keep them in separate routines, morning and night.
skinfrndly is educational and is not medical advice. Recommendations are generated from the answers you gave and general dermatological guidance — they cannot account for your full history. For persistent or severe skin conditions, or before starting anything new during pregnancy, speak to a doctor or dermatologist.