Delusional disorder — diagnosis, risk and management (MEQ)

(i) Diagnosis. Delusional disorder, mixed subtype (prominent persecutory and jealous themes), duration greater than 1 month, no prominent hallucinations, functioning relatively preserved at work, behaviour organised around delusional content. Alcohol is a comorbidity/amplifier, not a complete alternative explanation given the sustained multi-month systematisation. Partial-psychosis framing fits better than multi-domain schizophrenia.[1][4]

(ii) Differentials with discriminators.

(iii) Acute risk. Treat as high interpersonal violence risk (neighbour confrontation + Othello monitoring + “stop them before they stop me”). Same-day senior review; assess weapons/means; safety plan for wife and children; consider police/legal liaison if imminent risk; capacity and involuntary treatment under local statute if needed; alcohol brief intervention; do not send home with empty plan.[3][4]

(iv) Engagement and treatment. Alliance-first: validate distress, avoid collusion and humiliating challenge, shared goals (sleep, reduce confrontations, protect job/relationship). Offer antipsychotic — e.g. aripiprazole 5–10 mg oral daily, target often 10–15 mg, monitor akathisia and metabolic parameters; alternatives risperidone 1–2 mg titrating toward 2–4+ mg or olanzapine 5–10 mg with metabolic monitoring. Baseline FBC/U&E/LFT/glucose/lipids/ECG/BMI as for antipsychotic care. CBT-informed work when engageable; family work without triangulation; alcohol reduction plan; review acting-on-belief weekly initially.[5][6][3]

(v) Evidence honesty. Cochrane finds insufficient high-quality RCT evidence specific to delusional disorder to rank a definitive drug hierarchy — treat clinically with monitoring and broader psychosis evidence, without overclaiming DD-specific RCT certainty.[2]