Neuroleptic malignant syndrome induced by domperidone.

A 47-year-old woman with diabetic gastroparesis, on treatment with domperidone, a dopamine-receptor antagonist, was admitted to the hospital in coma, with high blood pressure and nonreactive pupils. She then developed high fever. Her condition progressively worsened for two days, when muscle rigidity was noted and creatine phosphokinase was greater than 2000 U/liter. A diagnosis of neuroleptic malignant syndrome was made, and the patient was given dantrolene with prompt and complete resolution of all signs and symptoms. Subsequent inquiry revealed a distant past history of positive muscle biopsy for malignant hyperthermia, obtained after the diagnosis had been made in a family member. This case suggests that domperidone may induce neuroleptic malignant syndrome and that patients with malignant hyperthermia are at increased risk for this complication.