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Allergic Skin Disorders

Picture of Photoallergic Reaction

Picture of Photoallergic Reaction

Photoallergic reactions occur when exposure to ultraviolet (UV) light alters the structure of a drug and stimulates the immune system to react. Sun-exposed areas of the skin display inflammation, resembling eczema. These reactions take some time to resolve. Affected skin is red, itchy, and swollen. Substances that may provoke photoallergic reactions include certain pain medications, chemotherapy drugs, fragrances, antimicrobials, and sunscreens.

Image Source: Color Atlas & Synopsis of Pediatric Dermatology Kay Shou-Mei Kane, Jen Bissonette Ryder, Richard Allen Johnson, Howard P. Baden, Alexander Stratigos Copyright 2002 by The McGraw-Hill Companies. All rights reserved.

Text Reference: Skin Cancer Foundation: "Phototoxic Reactions versus Photoallergic Reactions"