Medicines

Tretinoin

A prescription medicine in Korea. In a 1991 trial of 251 people, 79% of those using 0.05% for 24 weeks improved against 48% on vehicle. But in a 29-person trial in 2022, active and vehicle both improved 30–40% and could not be told apart.

Strong evidenceOver the counter — ask the pharmacist

Benzoyl peroxide

Benzoyl Peroxide

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.

Moderate evidencePrescription only

Adapalene

All 12 products registered in Korea are prescription-only. In a 67-person split-face trial, adapalene 0.3% with benzoyl peroxide 2.5% reduced scar counts by 15.5% over 24 weeks while the vehicle side increased by 14.4%.

Moderate evidenceOver the counter — ask the pharmacist

Azelaic acid

Azelaic Acid

All six products registered in Korea are over the counter. In a Cochrane review, azelaic acid beat placebo on participants' own assessments (three trials pooled, risk ratio 1.52), and a phase 3 trial of a 15% foam also beat vehicle. The review noted that most included studies were at high or unclear risk of bias.

Whether and how to use it is decided with a doctor or pharmacist.