From the Guidelines
Neuroleptic malignant syndrome (NMS) management involves primarily supportive care and removal of the initiating agent, with benzodiazepines as the first-line agent for agitation and external cooling measures for fever. The aetiology of NMS is primarily associated with dopamine receptor blockade, typically from antipsychotics like haloperidol, risperidone, or olanzapine, though it can also occur with antiemetics like metoclopramide 1. Key risk factors for NMS include coadministration of psychotropic agents, dehydration, physical exhaustion, preexisting organic brain disease, and the use of long-acting depot antipsychotics 1.
Management Strategies
- Immediate discontinuation of the offending agent
- Supportive care including IV fluids and monitoring of vital signs
- Benzodiazepines, such as lorazepam, for agitation 1
- External cooling measures for fever
- Consideration of reintroduction of the original precipitating drug may not lead to a reoccurrence of NMS, although patients with a history of NMS are at increased risk of recurrence 1
Complications and Monitoring
- Rhabdomyolysis
- Acute kidney injury
- Electrolyte abnormalities
- Respiratory compromise
- Monitoring for cardiorespiratory compromise and managing with standard supportive measures 1
Treatment Duration and Follow-Up
- Treatment typically continues for 7-10 days, with gradual tapering as symptoms resolve
- After recovery, if antipsychotic therapy is necessary, a different class should be selected, introduced at low doses after a 2-week washout period, with close monitoring 1
From the Research
Aetiology of Neuroleptic Malignant Syndrome
- Neuroleptic malignant syndrome (NMS) is a rare, potentially life-threatening antipsychotic-associated disorder 2
- It has been associated with virtually all neuroleptics, including newer atypical antipsychotics, as well as a variety of other medications that affect central dopaminergic neurotransmission 3
- The syndrome is characterized by fever, altered mental status, muscle rigidity, and autonomic dysfunction 3
- NMS can be induced by antipsychotic monotherapy 4
Management of Neuroleptic Malignant Syndrome
- Treatment includes immediately stopping the offending agent and implementing supportive measures, as well as pharmacological interventions in more severe cases 3
- Dantrolene, bromocriptine, and electroconvulsive therapy (ECT) are considered effective therapies for NMS, especially in severe cases 2, 5
- A combination of dantrolene and post-synaptic dopamine agonists may prove the most effective in this condition 5
- Supportive care, including symptomatic therapy, is also crucial in the management of NMS 2
- In some cases, patients may require mechanical ventilation and treatment for complications such as rhabdomyolysis and acute kidney failure 6
Therapy Regimens and Outcome
- No statistically significant differences regarding mortality rate or duration of treatment were found between dantrolene, bromocriptine, or ECT compared to supportive care in a systematic case series analysis 2
- However, a subgroup analysis showed that specific NMS pharmacotherapy (dantrolene, bromocriptine) and ECT were superior to purely symptomatic therapy in severe NMS cases 2
- ECT showed the lowest mortality rate in severe NMS cases 2
- Stricter criteria should be applied when diagnosing NMS in critical care and emergency medicine settings to ensure accurate diagnosis and effective treatment 6