Over-the-counter topical skincare products: a review of the literature.

Topical "anti-aging" products, with their seemingly limitless list of ingredients, make extensive claims to reduce wrinkles, fine lines, and sun damage, among others. Sales in the United States alone for cosmeceutical products are expected to increase by 7.4% per year to $8.2 billion by 2012. However, in this enormous industry, there has been a significant lack of rigorous controlled trials of efficacy. It is difficult for both dermatologists and consumers to make informed decisions in a market that is yet to be clearly defined and regulated. We elucidate the scientific basis for, as well as the literature behind, common active ingredients found in products intended to reverse photoaging, discuss some interesting new activities, and provide a review of several comprehensive studies on over-the-counter (OTC) products.