Sunscreens. Topical and systemic approaches for the prevention of acute and chronic sun-induced skin reactions.

In this article, practical and clinical aspects of photoprotection are discussed with emphasis on topical sunscreens. Protection against the adverse effects of sunlight includes prevention of the following: sunburn in normal individuals; acute phototoxic and photoallergic reactions; chronic skin damage (dermatoheliosis) and skin cancer; and specific disease-oriented responses (such as porphyria or polymorphous photodermatitis).