Neuroleptic Malignant Syndrome

Varadaraj R. Velamoor

Neuroleptic malignant syndrome (NMS) is a rare but potentially lethal form of drug-induced hyperthermia characterised by mental status changes, muscle rigidity, hyperthermia and autonomic dysfunction. Increased awareness and early recognition will lead to prompt management. The diagnosis of NMS presents a challenge because several medical conditions generate similar symptoms. The presentation and course of NMS can be quite variable ranging from a stormy and potentially fatal course to a relatively benign and self-limiting course. The most important aspect of treatment is prevention. This includes reducing risk factors (e.g. dehydration, agitation and exhaustion), early recognition of suspected cases and prompt discontinuation of the offending agent. All patients with psychosis should be monitored daily for dehydration and elevated temperature, have vital signs checked and agitation should be watched for. Antipsychotics should be used conservatively with gradual titration of doses. The management of NMS should be based on a hierarchy of symptom severity. Following an episode of NMS, the patient should be reassessed for further treatment with antipsychotics and rechallenge should not be attempted at least 2 weeks following resolution of symptoms of NMS. The patient and family should be educated about the episode and consent for further medication use obtained after a clear explanation of the risk-benefit analysis.