Updated May 08, 2014.

Definition: A rare, but life-threatening neurological disorder, usually caused by an adverse reaction to a neuroleptic (antipsychotic) drug.

Symptoms include:

• Extremely high fever
• Rapid heart rate
• Rapid breathing
• Rapidly fluctuating blood pressure
• Impaired consciousness
• Tremor
• Muscle rigidity and stiffness
• Catatonia

Neuroleptic Malignant Syndrome is potentially fatal. It is considered a medical emergency that often requires intensive medical intervention.