Ingredient Beauty BenefitsInternational non-proprietary name · Tretinoin
Tretinoin: it beat vehicle in a 251-person trial and was indistinguishable from vehicle in a 29-person one
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.
Last checked Sep 16, 2026
Tretinoin is retinoic acid itself. It does not need converting in the skin the way retinol does, which makes it the best-studied compound in the family.
And in Korea it is not a cosmetic. In the national drug register, Stieva-A cream at 0.01%, 0.025% and 0.05% are all listed as prescription-only. You cannot buy it without a prescription, and this page does not cover how to use it.
Results from this compound are often carried across when people read about retinol. They are different substances with different regulatory status.
What is established
79% improved in a 251-person trial, against 48% on vehicle
A randomised, double-blind, vehicle-controlled, multicentre study in 251 people with mild to moderate photodamaged facial skin, using 0.05% and 0.01% cream for 24 weeks.
Among those on 0.05%, 79% showed overall improvement against 48% of vehicle-treated controls. Fine wrinkling, mottled hyperpigmentation, roughness and laxity all fell significantly, and histology showed increased epidermal thickness.
A 2022 trial of the same compound on the chest went differently. Twenty-nine people used 0.05% lotion for 180 days, and both the active and the vehicle groups improved 30–40% — the blinded evaluator could not separate them.
Hence moderate on this site. The evidence is better than for most cosmetic ingredients, but there are two trials and one of them did not separate from vehicle.
- Randomised controlled trial in people · 251 participants · 24 weeks · Compared with vehicle (same formula minus the active) · Funding not declared · Endpoint scores from blinded assessors PMID 2024983
- Randomised controlled trial in people · 29 participants · 26 weeks · Compared with vehicle (same formula minus the active) · Funding not declared · Endpoint scores from blinded assessors PMID 35674757
Treated as contraindicated in pregnancy, while observational studies found no increase in risk
The 2026 systematic review and meta-analysis of first-trimester topical retinoid exposure pooled eight studies and 3,632,118 pregnancies, finding a risk ratio of 0.83 (95% CI 0.64 to 1.07) for major congenital malformations and 0.99 (0.68 to 1.43) for spontaneous abortion — no increase found.
These are pooled observational studies, and the authors note the result is driven by one large registry.
The teratogenicity of oral retinoids is established. And tretinoin is a prescription medicine, so if you are pregnant or planning to be, this judgement is made with the prescriber. It is not a decision to make alone.
- Observational study in people (8) · 3,632,118 participants · Compared with people not exposed · Funding publicly funded · Endpoint clinical events (cancers, lesion counts) PMID 42564875
In Korea it is prescription-only — 0.01%, 0.025% and 0.05%
In the Korean drug approval register, the topical products whose active ingredient is tretinoin are Stieva-A cream at 0.01%, 0.025% and 0.05%, and all three are classified as prescription-only (checked 16 September 2026).
It is not on the functional cosmetic list. The wrinkle-improvement actives in Annex 4, item 3 are retinol, retinyl palmitate, adenosine and polyethoxylated retinamide; tretinoin is not among them.
Known risks
- It irritates more than retinol. Redness, scaling, stinging and dryness are common.
- It is photosensitising, so sunscreen is required alongside.
- Use in pregnancy and breastfeeding must be discussed with the prescriber.
- On skin with dermatitis, eczema or rosacea it can make things worse.
What is not established
- Where the balance of benefit and risk settles over long-term use has no settled answer.
- Evidence for non-facial areas such as the chest and neck is thin, as above.
- Differences between concentrations: the trial above used 0.05% and 0.01%, but it was not designed to compare the two.
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