Psychotic Disorders
Diagnosis
Schizophrenia requires two or more core symptoms (delusions, hallucinations, disorganised speech, grossly disorganised or catatonic behaviour, negative symptoms) with at least one from the first three, plus functional decline and duration criteria. Know the differential: schizophreniform (1–6 months), brief psychotic disorder (<1 month with full return), delusional disorder (non-bizarre delusions, function preserved), schizoaffective (mood episodes with psychotic symptoms for ≥2 weeks in their absence), and substance/medication-induced psychosis.
Management
Acute psychosis: manage agitation safely, exclude organic causes (delirium, substance, medical), then antipsychotic. Treatment-resistant schizophrenia = inadequate response to two adequate antipsychotic trials; the answer is clozapine. Remember its monitoring and its specific indications (also suicidality and aggression).
Traps
- Diagnosing schizophrenia in the presence of prominent mood symptoms without checking the 2-week rule.
- Missing an organic cause in first-episode or late-onset psychosis.
- Forgetting that catatonia is treated with benzodiazepines (and ECT if malignant), not antipsychotics alone.
- Confusing postpartum psychosis (psychiatric emergency, immediate admission) with postpartum depression.
Worked example
A 24-year-old presents with 3 weeks of auditory hallucinations and persecutory delusions, no mood symptoms, function declining. Duration <1 month → brief psychotic disorder if full recovery occurs; if symptoms persist beyond 1 month, schizophreniform; beyond 6 months, schizophrenia.