What is the treatment for neuroleptic malignant syndrome (NMS)?

Treatment of Neuroleptic Malignant Syndrome

The primary treatment for neuroleptic malignant syndrome (NMS) is immediate discontinuation of the precipitating antipsychotic medication and providing aggressive supportive care. 1

Initial Management

• Discontinue the offending agent - The first and most critical step in NMS management is to immediately stop all antipsychotic medications 1, 2
• Provide supportive care which includes:
  • Treatment of agitation with benzodiazepines 1
  • Management of hyperthermia through cooling measures 1, 3
  • Address autonomic instability with IV fluids and other agents to normalize vital signs 1, 2
  • Monitor and manage complications such as rhabdomyolysis, metabolic acidosis, and renal failure 1

Pharmacologic Interventions

For severe cases of NMS (temperature >41.1°C or severe symptoms), specific pharmacologic therapy should be considered:

• Dopaminergic agents - Bromocriptine is most commonly used to address dopamine deficiency 1, 3
• Muscle relaxants - Dantrolene sodium may be used to reduce muscle rigidity and hyperthermia 1, 3, 4
• Benzodiazepines - For management of agitation and muscle rigidity 1, 5

Advanced Interventions for Severe Cases

• Emergency sedation, neuromuscular paralysis, and intubation may be required for cases with extreme hyperthermia (>41.1°C) 1
• Intensive care unit admission is necessary for approximately 25% of patients with NMS 1
• Electroconvulsive therapy (ECT) may be considered as a second-line treatment, particularly in severe cases not responding to pharmacologic interventions 4, 5

Monitoring and Management of Complications

• Laboratory testing should include complete blood count, electrolytes, renal function, liver function, creatine kinase, arterial blood gases, and coagulation studies 1
• Careful monitoring for complications such as:
  • Rhabdomyolysis with elevated creatine kinase
  • Metabolic acidosis
  • Elevated liver enzymes
  • Renal failure
  • Seizures
  • Disseminated intravascular coagulation 1

Treatment Based on Severity

• Mild to moderate NMS: Supportive care may be sufficient 4
• Severe NMS: A combination of specific pharmacologic therapy (dantrolene, bromocriptine) and supportive care has been shown to reduce mortality compared to supportive care alone 4

Important Considerations

• Avoid physical restraints as they may exacerbate isometric muscle contractions, worsening hyperthermia and lactic acidosis, thereby increasing mortality 1
• Monitor vital signs and hydration status daily in all patients on antipsychotics to prevent NMS 2
• Wait at least 2 weeks after resolution of NMS symptoms before considering rechallenge with antipsychotics 2

Outcomes

With proper treatment, mortality from NMS has decreased from 76% in the 1960s to less than 10-15% in recent years 1. Early recognition and prompt management are crucial for improving outcomes.