Fulminant metoclopramide induced neuroleptic malignant syndrome rapidly responsive to intravenous dantrolene

We report a case of fulminant neuroleptic malignant syndrome in a man aged 70 developing within 12 hours of starting six-hourly intravenous metoclopramide. The muscle rigidity and hyperpyrexia were unresponsive to intravenous benztropine but resolved within one hour of intravenous dantrolene 2 mg/kg. Within six hours the patient had a partial relapse which resolved completely following further intravenous dantrolene 2 mg/kg. This case demonstrates that the rapid effect of intravenous dantrolene can be life saving in fulminant neuroleptic malignant syndrome.