Neuroleptic malignant syndrome caused by dopamine-depleting drugs in a patient with Huntington disease.

Prior reports of neuroleptic malignant syndrome (NMS) concerned patients with psychiatric disorders, usually schizophrenia, who were taking dopamine receptor blocking agents. We report the syndrome in a patient with Huntington disease who was treated with dopamine-depleting agents. He had a negative evaluation for malignant hyperthermia (MH), and we suggest that NMS differs from MH. The occurrence of NMS caused by dopamine-depleting agents suggests that anticholinergic properties of phenotiazines are not the only cause. Central dopaminergic systems probably participate in thermoregulation, and dopamine depletion probably plays a pathogenetic role in this syndrome.