skip to main content

Cannabis use disorder with psychosis risk — MCCQE Part 1 MCQ

Instant feedback + full explanation. One question, done properly.

ModerateSubstance UseCannabis use disorder with psychosis riskMCCQE Part 1

A 20-year-old man using high-THC cannabis daily has one week of paranoia, auditory hallucinations and insomnia. He has no prior psychosis. He is calm and medically stable, but says a voice has told him to jump from a bridge. What is the best next step?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: A — Advise cannabis cessation and arrange urgent safety and first-episode psychosis assessment

The command hallucination creates an immediate self-harm concern, so urgent safety assessment and an appropriate emergency or first-episode psychosis evaluation are required. Cannabis, especially frequent high-THC use, can precipitate psychotic symptoms, and cessation is an important part of management. However, attributing symptoms to cannabis does not eliminate the need to assess suicide risk, other substances, medical causes, mood symptoms, functional decline and a possible primary psychotic disorder. First-presentation psychosis warrants specialist involvement and follow-up because some cannabis-associated episodes persist or precede a later psychotic disorder. Reassurance alone, delayed risk assessment and benzodiazepine monotherapy are unsafe.

Reference: Health Canada, Cannabis and Mental Health: https://www.canada.ca/en/health-canada/services/drugs-medication/cannabis/health-effects/mental-health.html; CAMH, Treating Psychosis: https://www.camh.ca/en/professionals/treating-conditions-and-disorders/psychosis