Neuroleptic Malignant Syndrome (NMS) is a rare life-threatening idiosyncratic reaction associated with the use of neuroleptics. It is characterized by delirium, muscular rigidity, fever and autonomic nervous system dysregulation. Its diagnosis represents a significant challenge for clinicians and many aspects regarding its epidemiology, etiopathology and nosology remain controversial.

Summarize current knowledge to facilitate NMS diagnosis and allow a fast onset of therapeutic and life-saving interventions.

Non-systematic review of the literature–scientific publications from Pubmed and a Psychiatry Textbook.

NMS typically develops during the first week after the neuroleptic is introduced, although it may also appear after years of treatment. Its incidence is of 0.02 to 3% in patients taking antipsychotics; the mean age of its patients is 50 years. Typical symptoms are muscle rigidity and temperature greater than 38hC in a patient on antipsychotic; however, recent reports indicate that these core symptoms may not always be present. Several risk factors have also been identified and must be addressed. NMS may be fatal in 10 to 20% of cases or may produce residual sequelae, like cognitive dysfunction or neurological deficits. NMS must be managed by aggressive use of supportive measures, as well as specific interventions. It recurs in 30% of patients, which can be diminished by specific measures.

NMS requires timely and accurate diagnosis and treatment. Antipsychotics should be used cautiously in patients at increased risk. When recognizing this condition, prompt withdrawal of the offending agent is the most important step. Wise approaches can diminish morbidity, mortality and recurrence.

The authors have not supplied their declaration of competing interest.