IS MELATONIN ASSOCIATED WITH THE DEVELOPMENT OF AUTOIMMUNE HEPATITIS

Melatonin is a neurohormone produced by the human pineal gland that pl ays a role in the regulation of many physiologic processes and has bee n proposed as a therapy for everything from insomnia to metastatic car cinoma. Melatonin is available in the United States without prescripti on. and adverse effects appear to be uncommon. However, because melato nin appears to have immunomodulatory properties, the potential exists for the development of autoimmune-related side effects. We describe a patient in whom characteristic clinical and laboratory features of aut oimmune hepatitis developed after beginning melatonin therapy for the treatment of insomnia, Liver biopsy demonstrated histologic features o f autoimmune hepatitis. Rapid symptomatic and biochemical improvement resulted from the initiation of immunosuppressive therapy; however, he patitis recurred after the withdrawal of steroid therapy. The temporal relation observed between melatonin use and the development of autoim mune hepatitis raises the possibility that the drug might be involved in the pathogenesis of this patient's autoimmune disease.