Photoaging and tretinoin.

Premature skin aging caused by repeated exposure to solar radiation is called photoaging. Although once considered an irreversible process, it is now established that photoaging can be treated by topical tretinoin. Both from carefully designed controlled clinical studies; and basic investigations into the mechanism by which tretinoin improves photoaged skin, our understanding of photoaging has been enhanced. This article highlights some of these studies which have contributed to our knowledge.