Psychosis associated with cannabis withdrawal: systematic review and case series
E. Chesney, Thomas J. Reilly, Fraser Scott, Ikram Slimani, Ananya Sarma, Daisy Kornblum, Dominic Oliver, Philip Mcguire
British Journal of Psychiatry December 3, 2024 DOI: 10.1192/bjp.2024.175 via Semantic Scholar
Summary
AI-generated from the abstractAbruptly stopping heavy, daily cannabis use can trigger psychosis, both in people experiencing their first episode and in those with a pre-existing psychotic disorder. A systematic review of 21 studies identified 44 individuals whose psychosis began after cannabis withdrawal, and a health-record search found another 68 cases. Almost all were daily users who stopped abruptly. Those who resumed cannabis after the acute psychotic episode were far more likely to relapse than those who abstained (odds ratio 13.9). The findings indicate that acute psychotic symptoms can emerge after cannabis cessation, not only during its use.
Study at a glance
| Characteristics | Systematic review and health-record study Case report Peer reviewed |
|---|---|
| Sample size | 112 |
| Population | Individuals whose psychosis followed cannabis withdrawal |
| Keywords | Medicine Psychology |
| Key finding | Abrupt cannabis withdrawal can trigger first-episode psychosis or relapse of existing psychosis, and resuming cannabis use after an episode greatly increases relapse risk. |
Abstract
Background Abrupt cessation of heavy cannabis use can cause a withdrawal syndrome characterised by irritability, anxiety, insomnia, reduced appetite and restlessness. Recent reports have also described people in whom cannabis withdrawal immediately preceded the acute onset of psychosis. Aims To identify cases of psychosis associated with cannabis withdrawal. Method We completed a systematic review of the literature, which comprised case reports, case series and other studies. We also searched a large electronic database of psychiatric healthcare records. Results The systematic review identified 44 individuals from 21 studies in whom cannabis withdrawal preceded the development of acute psychosis. In the health record study, we identified another 68 people, of whom 47 involved a first episode of psychosis and 21 represented further episodes of an existing psychotic disorder. Almost all people were daily cannabis users who had stopped using cannabis abruptly. Individuals who continued to use cannabis after the acute psychotic episode had a much higher risk of subsequent relapse than those who abstained (odds ratio 13.9 [95% CI: 4.1 to 56.9]; χ2 = 20.1, P < 0.00001). Conclusions Abrupt cannabis withdrawal may act as a trigger for the first episode of psychosis and a relapse of an existing psychosis. Acute psychotic symptoms can emerge after the cessation, as well as following the use, of cannabis.