Tretinoin
Retin-A · Retinoid (skin)
What it is
Prescription-strength retinoic acid — the gold-standard topical for photoaging and acne, and the compound every cosmetic "anti-aging" routine is quietly benchmarked against. Decades of evidence, pennies per use, and still outperforms almost everything sold above it.
What human evidence shows
As strong as topical dermatology gets: RCTs show improved fine wrinkles, texture and pigmentation over months, with histologic collagen increase. OTC retinol is a weaker prodrug of the same pathway — tretinoin is the evidence-bearing version.
Risks
The retinization period — weeks of dryness, peeling and irritation that makes most people quit exactly when it is starting to work. Photosensitivity (sunscreen becomes non-optional). Contraindicated in pregnancy. That is essentially the whole list, which is why it anchors this category.
Legal status
US: prescription-only topical; trivially available via dermatology telehealth.
Evidence base
established literature
Large human evidence base: several phase 3 or 4 trial reports, plus multiple meta-analyses or systematic reviews.
- phase 3/4
- 45
- randomised
- 579
- reviews
- 76
- human trials
- 1,153
Counts are of published papers, not distinct trials, and measure how much research exists — not whether this works or is safe for you.
Research (12)
- Comparing Tretinoin to Other Topical Therapies in the Treatment of Skin Photoaging: A Systematic ReviewAm J Clin Dermatol · 2024
- Topical tretinoin for treating photoaging: A systematic review of randomized controlled trialsInt J Womens Dermatol · 2022
- Tretinoin Review With Newer Formulations: Providing Effective and Tolerable Solutions in Clinical PracticeJ Drugs Dermatol · 2023
- Tretinoin peelingDermatol Surg · 2001
- Is tretinoin still a key agent for photoaging management?Mini Rev Med Chem · 2014
- Clindamycin/tretinoin: clindamycin phosphate/tretinoin gelDrugs R D · 2005
- Topical tretinoin research: an historical perspectiveJ Int Med Res · 1990
- Tretinoin tocoferil as a possible differentiation-inducing agent against myelomonocytic leukemiaLeuk Lymphoma · 1997
- Evaluating tretinoin formulations in the treatment of acneJ Drugs Dermatol · 2014
- Tretinoin therapy: practical aspects of evaluation and treatmentJ Int Med Res · 1990
- Topical tretinoin: its use in daily practice to reverse photoageingBr J Dermatol · 1990
- Tretinoin: a review of the nonclinical developmental toxicology experienceJ Am Acad Dermatol · 1997
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