Neuroleptic malignant syndrome is a life-threatening, neurological disorder most often caused by an adverse reaction to neuroleptic (antipsychotic) drugs. Symptoms include high fever, sweating, unstable blood pressure, stupor , muscular rigidity , and autonomic dysfunction . In most cases, the disorder develops within the first 2 weeks of treatment with the drug; however, the disorder may develop any time during the therapy period. The syndrome can also occur in people taking anti-Parkinsonism drugs known as dopaminergics if those drugs are discontinued abruptly.

Generally, intensive care is needed. The neuroleptic drug is discontinued, and the fever is treated aggressively. A muscle relaxant may be prescribed. Dopaminergic drugs, such as a dopamine agonist , have been reported to be useful.

Early identification of and treatment for individuals with neuroleptic malignant syndrome improves outcome. If clinically indicated, a low potency neuroleptic can be reintroduced very slowly when the individual recovers, although there is a risk that the syndrome might recur. Another alternative is to substitute another class of drugs for the neuroleptic. Anesthesia may be a risk to individuals who have experienced neuroleptic malignant syndrome.

From the public domain resource at http://www.ninds.nih.gov/health_and_medical/disorders/neuroleptic_syndrome.htm