Ingredient Beauty BenefitsInternational non-proprietary name · Benzoyl Peroxide
Benzoyl peroxide: in an analysis pooling 179 trials, it worked best combined with a retinoid
A network meta-analysis of 179 randomised trials and about 35,000 observations found that the most effective topical option for mild-to-moderate acne was a retinoid combined with benzoyl peroxide, reducing lesion counts by 26.16% more than placebo. In Korea, single-ingredient products are available over the counter.
Last checked Sep 16, 2026
Benzoyl peroxide is a topical medicine for acne. It is not a cosmetic, and it is not on Korea's list of functional-cosmetic acne actives — that list holds one entry, salicylic acid at 0.5%, restricted to rinse-off cleansers.
It is not on the prohibited-ingredients list either; we did not find it in Annex 1 of the Regulation on Safety Standards for Cosmetics. It is absent from the cosmetic column not because it cannot go in a cosmetic, but because products using it against acne are regulated as medicines.
What is established
Combined with a retinoid, it was the most effective topical option for mild-to-moderate acne
A network meta-analysis pooling 179 randomised controlled trials, roughly 35,000 observations and 49 treatment classes, published to May 2020. The outcome was percentage change in total lesion count from baseline.
For mild-to-moderate acne the most effective topical option was a retinoid combined with benzoyl peroxide — mean difference 26.16% against placebo (95% credible interval 16.75 to 35.36%).
Chemical peels (salicylic or mandelic acid) scored higher at 39.70% (12.54 to 66.78%), but with a far wider interval, and the authors noted the evidence there was more limited and warrants further research.
Oral treatments — antibiotics, hormonal contraceptives — did not appear effective for mild-to-moderate acne.
This is one of the rare entries on this site carrying strong evidence: 179 pooled trials, placebo comparison, and lesion counts as a clinical endpoint.
- Randomised controlled trial in people (179) · 35,000 participants · Compared with vehicle (same formula minus the active) · Funding not declared · Endpoint clinical events (cancers, lesion counts) PMID 35789996
In Korea, single-ingredient products are over the counter; antibiotic combinations are prescription-only
The Korean drug register lists 16 products with benzoyl peroxide as an active ingredient (checked 16 September 2026).
Single-ingredient products such as Benzac AC gel 2.5% are over the counter and can be bought at a pharmacy, while combinations with clindamycin such as Duac gel 3% and 5% are prescription-only.
The same substance is classified differently depending on what it is mixed with. The versions containing an antibiotic are controlled more tightly because of resistance.
Known risks
- It bleaches. Towels, pillowcases and clothing lose colour. Keep it off dyed hair too.
- Dryness, scaling, redness and stinging are common, which is why low strengths are the usual starting point.
- Severe hypersensitivity reactions are rare but reported. If your face swells or you have trouble breathing, stop and seek care immediately.
- Evidence that higher concentrations work better is not clear; the increase in irritation is.
What is not established
- The figure above belongs to the combination. The effect size of benzoyl peroxide alone is not the number quoted here.
- We found no established data on use during pregnancy. Ask a pharmacist or doctor.
- The balance of benefit and risk over long-term use is not settled.
Whether and how to use it is decided with a doctor or pharmacist.
What this article relies on
- 의약품안전나라 — 의약품등 정보검색 (품목 허가사항)식품의약품안전처 · Checked on 2026-09-16
- PubMed — 미국 국립의학도서관 문헌 데이터베이스National Library of Medicine · Checked on 2026-09-16