Neuroleptic malignant syndrome.

Neuroleptic malignant syndrome is a life-threatening reaction of neuroleptic medication. The estimated incidence rate of neuroleptic malignant syndrome is between 1% and 1.5% of patients treated with neuroleptics. The reported mortality rate varies from 11% to 38%. Risk factors include younger males (80% less than 40 years) and physical disability. Although 80% of neuroleptic malignant syndrome cases develop within the first 2 weeks of treatment, the syndrome can develop anytime during the therapy period. The clinical picture and laboratory findings are not always unique. Less than 50% of cases manifest with classical symptoms. Deaths usually result from cardiovascular collapse. Renal failure, pulmonary emboli, aspiration pneumonia, and respiratory failure are also reported. Familiarity with the syndrome, baseline laboratory values including creatine phosphokinase, lactate dehydrogenase, serum glutamicoxaloacetic transaminase, and complete blood cell count with a differential count, and a high index of suspicion are of the utmost importance in making the diagnosis of neuroleptic malignant syndrome. A judicial choice of neuroleptic medication and careful observation of patients may reduce the incidence, morbidity, and mortality of neuroleptic malignant syndrome.