Chlorpromazine photoallergy. Coexistence of immediate and delayed type

Abstract

A 54-year-old woman had a recurrent pruritic eruption in light-exposed areas. She had a combination of three types of hypersensitivity to chlorpromazine, ie, allergic contact dermatitis, photocontact dermatitis, and immediate allergic photosensitivity. Immediate wheal reactions were found after long-wave ultraviolet light irradiation at photopatch test and intradermal injection sites with chlorpromazine. These responses were differentiated from phototoxic reactions. A positive passive transfer reaction was also observed. To my knowledge, chlorpromazine photosensitivity of the immediate type has not been previously described.