Other cosmetics claim vitamin A as an ingredient, but these don't work like Retin-A, says dermatologist Dr. Charles R. Gaba of Louisville, Ky., who has been prescribing Retin-A for sun damage for two years. Over-the-counter preparations don't contain vitamin A acid, he says; ``it would be like rubbing water on your skin.''

Kligman, professor of dermatology at the University of Pennsylvania, developed Retin-A 17 years ago as an acne treatment. Now studies show it removes wrinkles and reverses the skin's sun damage. That news, reported Friday, set dermatologists' phones ringing across the nation. And Kligman is the beauty and youth-seekers' accidental hero.

Kligman's biggest worry about all the Retin-A furor, he says, ``is that this is being blown out of proportion. Retin-A doesn't stop people from getting old and won't reverse the deep wrinkles of older people.''