Tretinoin

Tretinoin is retinoic acid, the biologically active form of vitamin A that skin can use directly without the conversion steps required by milder derivatives such as retinol and retinaldehyde. Because it acts on skin cells without that conversion, it is considered a potent retinoid and, in most markets, is a prescription-only medicine.

Tretinoin belongs to the retinoid family and is generally described in the context of texture, signs of photoaging, and acne. As a prescription product it is intended to be used under the direction of a clinician or dermatologist, who determines whether it is appropriate, at what strength, and how it should fit into a routine. This entry does not provide dosing or usage instructions; those decisions belong with a prescriber and the product's own labeling.

A few general points are widely noted. Because it is strong, tretinoin commonly causes dryness, redness, peeling, and irritation, particularly in the early weeks as skin adjusts, and it can increase sun sensitivity, so daytime sun protection is typically emphasized. It is contraindicated in pregnancy, and use during pregnancy or breastfeeding should be discussed with a doctor. Anyone considering tretinoin, or experiencing persistent irritation from it, is best served by consulting a qualified healthcare professional rather than self-directing treatment.