Photoallergen

An antigen formed in the skin by photochemical (short-wave light, UV radiation) modification of a photosensitive prohapten to the hapten and via its connection with a protein in the skin. The prohapten can enter the skin exogenously or endogenously. Drugs, cosmetics and body care products are the most well-known photoallergens (see table).

• A photo patch test is performed to identify photo contact allergens in photosensitization.
• Systemic photosensitizers (see table) must be detected by systemic photoprovocation.

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4. Fujita H et al. (1965) Five cases presenting with diffuse erythema and edematous papules possibly caused by saccharin, Acta Derm (Kyoto) 60: 303
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6. Hölzle E et al. (1991) Photopatch testing: the five-year experience of the German, Austrian, and Swiss photopatch test group. J Am Acad Dermatol 25: 59–68
7. Lugović-Mihić L et al. (2017) Drug-Induced Photosensitivity—A Continuing Diagnostic Challenge. Acta Clin Croat 56:277–283.
8. Moore DE (2002) Drug-Induced Cutaneous Photosensitivity: Incidence, Mechanism, Prevention, and Management. Drug Saf 25: 345–372
9. Schauder S (2003) Solar urticaria. Hautarzt 54: 952–958
10. Scheman A (2000) Adverse reactions to cosmetic ingredients. Dermatol Clin 18: 685–698
11. Schempp CM et al. (2002) Plant-induced toxic and allergic dermatitis (phytodermatitis). Hautarzt 53: 93–97
12. Taub SJ (1972) Adverse reactions to saccharin. Eye Ear Nose Throat Mon 51: 405-406

Photoallergenic Substances (Selection)