Neuroleptic malignant syndrome: fever, lead-pipe rigidity, autonomic instability, altered mental state and a raised CK. Stop the antipsychotic, cool, rehydrate, and admit (consider dantrolene or bromocriptine with specialist advice).
Acute extrapyramidal effects
- Acute dystonia (oculogyric crisis, torticollis): IM procyclidine
- Akathisia (inner restlessness): reduce dose, consider propranolol
- Parkinsonism: reduce dose or add an anticholinergic cautiously
- Tardive dyskinesia with long-term use: review the drug
Other important effects
- Metabolic: weight gain, diabetes, dyslipidaemia (especially olanzapine, clozapine)
- Hyperprolactinaemia (galactorrhoea, sexual dysfunction; especially risperidone)
- QT prolongation (especially haloperidol); VTE risk
- Clozapine: agranulocytosis, myocarditis, constipation (can be fatal), seizures
Common / monitor
- Weight gain, sedation, metabolic
- EPSEs: akathisia, parkinsonism
- Monitor glucose, lipids, ECG
Needs action
- Acute dystonia: procyclidine
- Hyperprolactinaemia, QTc prolongation
- Review dose or switch agent
NMS (emergency)
- Fever, rigidity, autonomic instability, high CK
- Stop antipsychotic, supportive care
- Critical care; dantrolene or bromocriptine
Monitoring plan
1
1. Baseline
Weight and BMI, waist, pulse and BP, fasting glucose or HbA1c, lipids, prolactin, LFTs, and an ECG if cardiac or QT risk.
Weight and BMI, waist, pulse and BP, fasting glucose or HbA1c, lipids, prolactin, LFTs, and an ECG if cardiac or QT risk.
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2
2. Ongoing
Repeat metabolic monitoring at 12 weeks, at 1 year, then annually (weight more often early). Follow the NICE schedule.
Repeat metabolic monitoring at 12 weeks, at 1 year, then annually (weight more often early). Follow the NICE schedule.
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3
3. Manage effects
Treat extrapyramidal effects, switch to a lower-risk agent for troublesome metabolic or prolactin effects, and manage cardiovascular risk.
Treat extrapyramidal effects, switch to a lower-risk agent for troublesome metabolic or prolactin effects, and manage cardiovascular risk.
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4
4. Clozapine
Mandatory FBC monitoring for neutropenia, plus monitoring for myocarditis and constipation.
Mandatory FBC monitoring for neutropenia, plus monitoring for myocarditis and constipation.
NMS vs serotonin syndrome
- NMS: slower onset, rigidity with hyporeflexia, after antipsychotics
- Serotonin syndrome: rapid, clonus and hyperreflexia
- Both: hyperthermia, raised CK, autonomic instability
Pitfalls
- Missing NMS or dismissing a raised CK
- No metabolic monitoring on long-term treatment
- Missing clozapine myocarditis or constipation
- Combining QT-prolonging drugs
MedPrep - www.medprep.uk - Educational revision aid only. Not clinical guidance. Doses are adult examples; check the BNF, current guidelines and local policy, and seek senior advice. Nov 2026