SAQ 220 – Toxicology – neuroleptic malignant syndrome

Question 9. neuroleptic malignant syndrome.

a. Cardinal features

• Neuromuscular rigidity.
• Altered mental status.
• Autonomic instability.

b. Risk factors

• High neuroleptic dose or recent large dose increase.
• Parenteral administration or use of multiple neuroleptics.
• Haloperidol or depot fluphenazine.
• Young age, male sex, psychiatric comorbidity, dehydration, trauma, infection, or malnutrition.

c. Antidotes

• Bromocriptine.
• Dantrolene.

d. Management

• Stop dopamine-antagonist drugs.
• Use RSI and ventilation if severe rigidity compromises ventilation or severe hyperthermia is present.
• Correct hyperthermia, including neuromuscular paralysis where required.
• Correct hypoglycaemia and other physiological derangements.
• Treat hypertension and tachycardia with an appropriate vasodilator.
• Consider benzodiazepines.