Acute Behavioural Disturbance in a Patient with Suspected Stimulant Intoxication
A 24-year-old man is brought by police after being found agitated, sweating and shouting in the street. He is tachycardic at 148, BP 168/98, temperature 38.9°C, pupils dilated, and he is combative and not answering questions. There is no history available. He has no visible injuries. The department is busy and there is one security officer on shift. A nurse suggests physical restraint and a large dose of haloperidol.
1. Outline your immediate priorities and the reasoning behind them.
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Recognise this as a medical emergency with risk of sudden collapse (hyperthermia, rhabdomyolysis, arrhythmia), not simply a behavioural problem.
- Safety first: ensure adequate staff, clear the area of hazards, and use verbal de-escalation. If restraint is needed, use the minimum necessary and monitor continuously - prone restraint and sustained struggle are associated with asphyxia and sudden death.
- ABCs and monitoring: oxygen, continuous cardiac monitoring, IV access, and a capillary glucose. Check temperature, pupils and focal neurology.
- Sedation for severe agitation: a benzodiazepine is generally first-line for undifferentiated agitation and stimulant toxicity (e.g. lorazepam or midazolam, titrated). Antipsychotics such as haloperidol can be used cautiously but lower the seizure threshold and may impair temperature regulation; a large empirical dose is unwise before assessment.
- Cooling: active cooling for hyperthermia, antipyretics are less effective in drug-induced hyperthermia.
- Investigations: glucose, electrolytes, renal function and creatine kinase, ECG (QRS/QT), and consider toxicology screening.
- Reassess frequently; document capacity and the legal basis for any restraint or treatment.
2. What is your differential diagnosis, and how would you distinguish the key possibilities at the bedside?
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Differential: stimulant intoxication (cocaine, amphetamines, cathinones), anticholinergic toxicity, serotonin syndrome, neuroleptic malignant syndrome, alcohol or benzodiazepine withdrawal, hypoglycaemia, head injury, sepsis/encephalitis, thyroid storm and acute psychosis.
Bedside discriminators:
- Anticholinergic toxicity: dry skin, flushing, urinary retention, 'dry as a bone' - stimulants usually cause sweating.
- Serotonin syndrome: clonus (especially ankle), hyperreflexia, agitation, diarrhoea, and a history of serotonergic drugs.
- NMS: rigidity ('lead-pipe'), bradyreflexia, recent antipsychotic use, and a slower onset over days.
- Sympathomimetic/stimulant: sweating, dilated pupils, tachycardia, hypertension, agitation.
- Hypoglycaemia: check glucose immediately - reversible and easily missed.
- Head injury/sepsis: focal neurology, meningism, source of infection, temperature pattern.
Use history from collateral sources, a drug history and a thorough physical examination, including skin, pupils, reflexes and temperature.
3. The patient becomes less agitated after sedation but then develops a temperature of 40.2°C, rigidity and a rising creatine kinase. What is your management?
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This suggests progression to a hypermetabolic state (stimulant-induced hyperthermia, serotonin syndrome or NMS).
- Aggressive cooling: ice packs, cold IV fluids, and consider intubation and paralysis with ventilatory support if cooling fails or there is instability.
- Benzodiazepines for agitation and muscle activity; if rigidity is prominent, consider dantrolene (NMS) or bromocriptine as appropriate, in consultation.
- Stop the offending agent and review all medications.
- IV fluids and urine output monitoring to prevent rhabdomyolysis-induced renal failure; consider urinary alkalinisation in severe cases per local protocol.
- Treat complications: arrhythmias (avoid agents that prolong QT), seizures, hyperkalaemia, and coagulopathy/DIC.
- ICU referral and continuous monitoring; document the timeline and interventions.