A 34-Year-Old with First-Episode Psychosis and Agitation in a General Hospital
A 34-year-old man is brought to a general hospital emergency department by police after he was found shouting in the street, saying his neighbours are poisoning him through the water supply. He has not slept for 3 nights, is pacing, and has not eaten. He is sweating, his pupils are dilated, and he appears to be responding to voices. Temperature is 37.4°C, pulse 112/min, blood pressure 140/90 mmHg. He is wary but answers questions, saying he is "fine" and does not want to be here. He has no known psychiatric history and no regular medication. His brother says he has been using "something" at parties for a few months, but does not know what. There is no psychiatric inpatient bed available for 24 hours, and the hospital has a psychiatric liaison nurse by day only.
1. What is your differential diagnosis, and what would you prioritise in the first hour?
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The differential spans psychiatric and medical causes, and the first priority is to exclude a medical cause for acute psychosis and agitation.
Differential:
- Substance-induced psychosis: stimulants (amphetamine, cocaine), cannabis, synthetic cannabinoids, or alcohol or benzodiazepine withdrawal. The sweating, dilated pupils, tachycardia and party drug history fit a stimulant toxidrome.
- Primary psychotic disorder (e.g., schizophrenia or schizoaffective disorder), possibly first episode.
- Delirium from a medical cause: sepsis, hypoglycaemia, head injury, metabolic derangement, or drug toxicity - the fluctuating attention and autonomic features require exclusion.
- Bipolar disorder with mania and psychotic features: sleeplessness, agitation, grandiosity or persecutory delusions.
- Other: thyrotoxicosis, steroid or other drug effects, epilepsy, encephalitis, or poisoning.
First hour: ensure safety of staff and patient, use a calm low-stimulus approach, check capillary glucose, temperature, pulse, blood pressure, oxygen saturation, and perform a focused neurological and general examination; obtain bloods including full blood count, urea and electrolytes, liver function, thyroid function, and urine and blood toxicology if possible. Do not assume psychiatric cause before these are done.
2. He becomes increasingly agitated and says he will leave. He has capacity to make some decisions but is clearly unwell. What legal and ethical framework guides your next steps, and how would you manage his agitation?
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This is a capacity and risk problem. I would assess his capacity to make the decision to leave, focusing on whether he understands, retains, weighs and communicates the relevant information - including the risk to himself and others from untreated psychosis and possible intoxication.
If he lacks capacity for that decision, and there is a serious risk to his health or safety or to others, the appropriate legal framework depends on jurisdiction: mental health legislation (which may permit detention for assessment and treatment) or, where the cause is primarily medical, the general incapacity framework. I would involve the psychiatric liaison nurse, the on-call psychiatrist, and hospital security, and document the assessment carefully. I would not physically restrain him without a clear legal basis and clinical plan.
For agitation:
- De-escalation first: calm environment, short sentences, offer food and drink, avoid confrontation and crowding.
- Treat reversible causes: fluids, glucose if low, and manage the suspected intoxication.
- Pharmacological sedation if de-escalation fails and there is risk: a benzodiazepine or antipsychotic, chosen with caution because of possible stimulant intoxication and unknown medical status; monitor for respiratory depression and neuroleptic malignant syndrome, and avoid polypharmacy.
- Close observation and a safe environment while awaiting psychiatric assessment.
The key judgement is that "he wants to leave" does not end the assessment; capacity and risk must be actively assessed and the legal pathway followed.
3. The next morning he is calm but still believes the water is poisoned, and the liaison nurse says no bed will be available for 24 hours. How would you plan his care and follow-up?
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He is now settled but still has a fixed persecutory delusion, which is a significant risk factor and requires ongoing psychiatric care. The absence of a bed does not mean discharge without a plan.
Plan:
- Keep him under observation in a safe environment, with regular mental state examination, and involve the on-call psychiatrist for a formal assessment and diagnosis. Clarify the role of substances with toxicology and history.
- Assess risk explicitly: risk to himself (self-neglect, dehydration, fear-driven behaviour), risk to others (retaliation against neighbours), and vulnerability. Document the assessment.
- Start or plan treatment: antipsychotic medication should be initiated or recommended by psychiatry, with baseline investigations and monitoring; treat any withdrawal or intoxication.
- Arrange a clear disposition: if he is to remain in hospital, document the legal basis; if discharge is being considered, ensure urgent psychiatric follow-up, involvement of the family or brother, crisis contact numbers, and a safety plan, and consider whether he meets criteria for detention if risk is high.
- Communicate with the brother and, with consent, the family, about warning signs and how to seek help.
- Follow up the substance use, which may be driving or complicating the psychosis.
The judgement is that a settled patient with an untreated delusion is not a discharged patient, and that a bed shortage must be managed with a documented risk plan rather than by default.