Dermatitis herpetiformis (DH) is a chronic, pruritic, papulovesicular dermatosis on extensor surfaces that is characterized by a neutrophilic infiltrate and granular immunoglobulin A deposition at the dermal papillae. Although the presence of immunoglobulin A in the skin and the severity of DH are known to be associated with gluten intake, few drugs have been implicated in the induction of DH. We report a case of DH triggered by intramuscular injections of leuprolide acetate, a gonadotropin-releasing hormone analog, in a patient with a history of prostate cancer.