Abstract
A 80-year-old woman developed diffuse edematous infiltrative erythematous dermatitis over her face, neck, breast and extremities following ingestion of cyproheptadine hydrochloride. A biopsy of the skin lesion revealed a lichenoid tissue reaction. While the closed patch test of cyproheptadine hydrochloride was negative, the photopatch test was positive. The action spectrum for the photosensitivity was under 320nm, within the absorption spectrum of cyproheptadine hydrochloride. One year later, the closed patch test of cyproheptadine hydrochloride became positive.
