Tretinoin, also known as all-trans retinoic acid [1], is the prescription-strength retinoid that everything else in the vitamin A family gets compared to. Dermatologists have been prescribing it for over 50 years for acne, and along the way it picked up the strongest anti-aging evidence of any topical ingredient: faded dark spots, softened wrinkles, and genuinely improved skin texture.
It's also strong enough to wreck your skin barrier if you use it carelessly, and easier than ever to buy from online pharmacies without much guidance. So here's the honest guide: what tretinoin does, how it compares to retinol, and how to use it without spending your first two months red and peeling.
A note for UK readers: tretinoin is prescription-only here. GPs occasionally prescribe it for acne (usually as Treclin, a tretinoin and clindamycin combination gel), but for anti-aging use you'll generally need a private dermatologist or a regulated online pharmacy. Wherever you get it, get it with a prescription; unregulated imports are a gamble on what's actually in the tube.
Tretinoin vs retinol: what's the difference?
Retinoids are a family of vitamin A compounds, and the key difference between them is how much conversion they need before your skin can use them.
Tretinoin is retinoic acid, the active form, so it works at full strength on contact. Retinol has to be converted into retinoic acid by your skin first, which makes it meaningfully weaker and gentler. That's the whole trade-off: tretinoin delivers faster, stronger results with more irritation; retinol delivers slower, milder results with less.
For most people starting out, retinol is the right first step. Tretinoin earns its place for stubborn acne, established sun damage and pigmentation, or when a couple of years of retinol has stopped moving the needle.
What tretinoin actually does
The evidence base here is unusually good. With consistent use, tretinoin:
- Clears stubborn acne, including blackheads, whiteheads and closed comedones
- Fades dark spots and hyperpigmentation
- Softens fine lines and wrinkles by boosting collagen production
- Speeds up skin cell turnover, improving texture and evening out skin tone
- Reduces the inflammation driving breakouts
It's helped millions of people with skin that nothing over the counter would shift. It just asks for patience and a bit of technique in return.
How to use tretinoin
Tretinoin typically comes in 0.025%, 0.05% and 0.1% strengths, in cream or gel form. Start at 0.025%, and if you're acne-prone, lean towards the gel; some cream bases are richer than oily skin appreciates.
Two rules before anything else. First, evenings only; tretinoin degrades in sunlight and makes your skin significantly more sun-sensitive, so daily SPF 30+ becomes non-negotiable for as long as you use it. Second, start at two to three nights a week and build up slowly. Almost every bad tretinoin experience comes from doing too much, too soon.
The routine itself:
- Cleanse gently. No acids or exfoliants on tretinoin nights; the medication provides all the exfoliation your skin needs and then some.
- Wait 20 to 30 minutes for your skin to dry completely. Applying tretinoin to damp skin increases absorption, which sounds good but in practice just means more irritation.
- Use a pea-sized amount for the whole face. Genuinely pea-sized. Dot it across the forehead, cheeks and chin, then spread. More product doesn't work faster; it peels harder.
- Wait another 15 to 20 minutes, then moisturise. Tretinoin is drying, and a good ceramide moisturiser is what keeps the process comfortable. CeraVe Moisturising Cream is the standard recommendation for a reason.
- Struggling with irritation? Try the sandwich method. A thin layer of moisturiser before the tretinoin and another after blunts the harshness without cancelling the benefits. It's the best trick there is for sensitive skin.
Keep it well away from the eye area, the corners of the nose and the lips, where the skin is thinnest and irritation hits hardest.
Side effects and how to manage them
The purge is real, and it's temporary. For the first few weeks, acne can get worse before it gets better, as the accelerated cell turnover pushes brewing congestion to the surface. A typical purge lasts around four weeks, sometimes six to eight. It's the medication working, not failing, but it's demoralising if nobody warned you.
Peeling and dryness peak early. The first three to four weeks are the flaky ones. Keep moisturising, don't pick at flakes, and resist the urge to exfoliate them away; that's how a rough patch becomes a damaged barrier.
Dial back if you need to. Persistent burning, blistering, swelling or scabbing isn't part of the process. Drop the frequency, try the sandwich method, or step down a strength, and speak to the prescriber if it continues.
Results take months. Acne improvement usually shows around the three-month mark. The anti-aging benefits, collagen rebuilding, softened lines, faded pigmentation, build over six months to a year and keep improving beyond that. Tretinoin rewards the patient and punishes the sporadic.
Frequently Asked Questions
How long before I see visible results?
Around three months for acne, and three to six months for texture and pigmentation, with the full anti-aging benefits arriving after a year or more of consistent use.
Can tretinoin be used every day?
Eventually, if your skin tolerates it. Start at two to three nights a week and increase gradually over a couple of months. Plenty of people stay at every-other-night forever and still get excellent results.
What products should I avoid alongside tretinoin?
On tretinoin nights, skip AHAs (glycolic, lactic), BHAs (salicylic acid), benzoyl peroxide, vitamin C and every other exfoliant, physical or chemical. Keep those for the mornings or for non-tretinoin evenings once your skin has adjusted.
Can I use tretinoin if I have sensitive skin?
Cautiously. Start at 0.025%, twice a week, with the sandwich method from night one. If your skin is reactive at baseline, consider building tolerance with retinol first.
Can tretinoin be used around the eyes?
The skin there is much thinner, so most people should keep a fingertip's distance from the orbital bone. Dry eyes are a commonly reported side effect of applying too close.
Can tretinoin be used while pregnant?
No. Tretinoin should not be used during pregnancy or while trying to conceive. Azelaic acid is the usual pregnancy-safe alternative for both acne and pigmentation; ask your GP or dermatologist.
What's the best moisturiser to use with tretinoin?
A fragrance-free cream with ceramides and hyaluronic acid. CeraVe Moisturising Cream is our pick, with Eucerin's urea creams a close second for very flaky phases.
Can I apply tretinoin to my neck?
Yes, but the neck is thinner-skinned than the face, so halve the frequency: every other night at most, and moisturise generously.
What happens if I stop using tretinoin?
The benefits fade gradually. Acne can return if that's what you were treating, and the collagen-boosting effects taper off over months. Faded sun spots generally stay faded, provided you keep up the sunscreen that stops them re-forming.
How long does a tretinoin purge last?
Usually around four weeks, occasionally six to eight for more congested skin. If your skin is still consistently worse than baseline at the two-month mark, check in with your prescriber.
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