Retinol

Retinol is 视黄醇 (shì huáng chún) in Chinese — 視黃醇 in Traditional Chinese (Taiwan) — and is commonly marketed as A醇 (A chún). It's the vitamin A derivative used to speed skin cell turnover and soften fine lines and wrinkles.

There's an adjustment period of roughly 2-4 weeks — mild redness, flaking, or dryness is normal. Start at a low concentration, 2-3 nights per week, and increase gradually. Once your skin adapts, the barrier actually ends up stronger.

Tretinoin is stronger, faster-acting, harsher on skin, and prescription-only. Retinol is much gentler: slower results, better tolerated, fine for home use. It has to convert inside the skin before it works, which is what makes the process milder.

Not recommended. Transdermal absorption of topical retinol is low, but to be safe, avoid it entirely during pregnancy and breastfeeding. Start again afterward.

Absolutely. Retinol increases your skin's sensitivity to UV, making tanning and sunburn more likely. Wear SPF 30+ during the day, and apply retinol at night for best results.

Expect 4-8 weeks for visible improvement, and 3+ months of consistent use for real anti-wrinkle effects. Don't look for dramatic changes within a week or two — patience is the whole game.