Ingredient Beauty BenefitsInternational non-proprietary name · Adapalene
Adapalene: atrophic scars fell 15.5% in 24 weeks while the vehicle side rose 14.4%
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%.
Last checked Sep 16, 2026
Adapalene is a topical retinoid medicine. It belongs to the same family as retinol and tretinoin but has a different structure, which makes it more stable in light and air.
In Korea it is prescription-only. All twelve products in the national register with adapalene as the active ingredient are classified that way. Some countries sell it over the counter; Korea does not.
What is established
On one face, one side lost scars and the other gained them
A multicentre, randomised, investigator-blinded trial in 67 people with moderate or severe facial acne (25 or more inflammatory lesions, ten or more atrophic scars). Adapalene 0.3% plus benzoyl peroxide 2.5% gel went on one half of the face and vehicle on the other, daily for 24 weeks.
At baseline each half-face averaged about 40 lesions and 12 scars. By week 24 the total scar count had fallen 15.5% on the active side and risen 14.4% on the vehicle side — roughly a 30-point difference, a mean of 9.5 versus 13.3 scars per half-face (P < .0001).
Comparing the two sides of one person's face leaves little room for individual variation. But there were 67 participants, and what was tested was not adapalene alone but a combination with benzoyl peroxide.
That scars increased on the vehicle side may matter more than that they fell on the active side. Untreated acne was busy leaving scars during those months.
- Randomised controlled trial in people · 67 participants · 24 weeks · Compared with vehicle (same formula minus the active) · Funding not declared · Endpoint scores from blinded assessors PMID 29549588
All 12 products registered in Korea are prescription-only
The Korean drug register lists 12 products with adapalene as the active ingredient, all prescription-only (checked 16 September 2026). Differin gel 0.1% is among them.
It is not on the functional cosmetic list. The only listed acne active is salicylic acid at 0.5%, restricted to rinse-off cleansers.
Some people obtain it through personal importation. Products acquired that way sit outside the controls attached to the Korean registration.
Known risks
- Dryness, scaling, redness and stinging are common in the first weeks — the family trait of retinoids.
- It is photosensitising, so sunscreen is required alongside.
- Use in pregnancy must be discussed with the prescriber. The state of the evidence for topical retinoids is on the tretinoin page.
- On skin with eczema or dermatitis it can make things worse.
What is not established
- The trial above tested a combination. The effect size of adapalene alone on scarring is not this number.
- Nothing on this page compares 0.1% against 0.3% directly.
- What happens to scars after 24 weeks is not something this trial answers.
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