Cannabis use and psychosis

Meet the patient

An 18-year-old apprentice arrives at 11pm with his mother. For eight months he has smoked high-potency cannabis nightly. For three weeks he has been certain that his foreman keeps a file on him and reads his messages.[6][13]

He is frightened rather than flat, has barely slept in a week, and stopped turning up to work on Monday. Last joint: yesterday evening. Urine screen positive for cannabis and nothing else. Observations normal.[12][19]

His mother offers the line you will hear a thousand times: "It's only weed." The resident writes cannabis-induced psychosis, discharge when settled. The examiner will not ask you whether cannabis is harmful. The examiner will ask: "Which layer is this, and what have you booked for the next five years?"[4][9]

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