Dermatological toxicity has been reported following initiation of therapy with minoxidil, but no cases have been reported following prolonged use. We report the emergence of an erythematous weeping rash with impending exfoliation three years after the initiation of minoxidil therapy. Minoxidil was withdrawn and the patient responded to therapy with topical corticosteroids. Following minor surgery, the patient was inadvertently rechallenged with minoxidil. Within 24 hours of exposure bullous lesions reappeared in the extremities which again resolved with topical corticosteroids. Dermatological lesions observed on this patient were similar to those reported following acute minoxidil exposure and strongly implicate chronic minoxidil therapy.