Retin-A is a trademarked brand name for Tretinoin, a retinoic acid cream used to treat acne and keratosis pilaris; it is claimed that it stimulates skin cell turnover and smoothes wrinkles. It is used by some as a hair loss treatment.

GoldBamboo

... TRETINOIN (Altinac™, Avita™, Renova®, Retin-A®, Retin-A® Micro™) is a naturally occurring form of vitamin A. It is applied to the skin to treat mild to moderate acne or to treat the effects of aging on the face, such as fine lines, wrinkles, or "age spots". Generic tretinoin cream, liquid, and gel are available. ...
Drug Digest - more...

Tretinoin Systematic (IUPAC) name 3,7-dimethyl-9-(2,6,6-trimethyl ...
Wikipedia - [full article]

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