Tretinoin (all-trans retinoic acid)
Skin/Hair · Retinoid — RAR agonist
Tier A
What this is
Only topical anti-aging ingredient with unambiguous RCT evidence for reversing photoaging (Kligman tradition). Adapalene is the closest OTC alternative. Apply to completely dry skin (wet skin increases irritation) and use sunscreen daily. Expect 3-6 month adjustment period; 'retinization' through initial irritation is normal.
Mechanism
Active metabolite of vitamin A; binds retinoic acid receptors (RARα/β/γ); normalizes follicular keratinization, increases collagen synthesis, thickens epidermis, fades dyspigmentation
Dose & route
0.025-0.1% topical cream/gel nightly on dry skin; start 2-3x/week and build tolerance
Citations
- https://pubmed.ncbi.nlm.nih.gov/3286781/
- https://pubmed.ncbi.nlm.nih.gov/17515510/
- https://pmc.ncbi.nlm.nih.gov/articles/PMC2699641/
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This is an independent synthesis of published research by a non-clinician. Scores are opinions supported by citations, not prescriptions. See the full disclaimer and methodology for how this score was produced and what it does and doesn't mean.