Neuroleptic Malignant Syndrome

NEUROLEPTICS are useful medicines widely used to control psychosis and agitation. They have numerous side effects, including little-understood ones such as tardive dyskinesia and neuroleptic malignant syndrome (NMS). The latter is a rare side effect of most neuroleptics, including haloperidol, fluphenazine decanoate, and chlorpromazine. The occurrence of NMS does not seem to be related to dose or drug interactions. It is more likely to occur in young men, patients with brain disorders, and persons treated with depot-injection preparations, while heat stress, physical exhaustion, or dehydration may predispose to the syndrome.¹⁻³Findings include hyperpyrexia, rigidity, dysphagia, dyskinesia, akinesia, delirium, sialorrhea, tachypnea-dyspnea, tachycardia, labile hypertension, cardiac arrhythmias, elevation in creatine kinase and liver function values, and respiratory acidosis.³Death rates range from 20% to 38%, and death may occur because of complications such as cardiac arrhythmias, myocardial infarction, thromboembolism, aspiration pneumonia, respiratory failure, and rhabdomyolysis with myoglobinuria and acute renal