Topical retinoid therapy can prevent the hyperproliferation of keratinocytes and reduce the release of proinflammatory cytokines. The three most commonly used retinoids are tretinoins, tazarotene, and adapalene. Adapalene is the most effective and best tolerated; it is available in different concentrations and in different vehicles, such as gels, lotions, and creams. This treatment can cause a primary irritant dermatitis, manifested as erythema and dryness. Start with the lowest concentration possible.