Review examines the complex overlap between cannabis use and psychosis in young people | Research

The takeaway

Cannabis use increases risk for both attenuated and acute psychotic symptoms in youth, may worsen psychosis in those with underlying vulnerability, and treatment approaches that integrate substance use with psychosis care are most promising.

Child and adolescent psychiatrists, early psychosis intervention teams, school counselors, and parents of at-risk youth.

Cannabis increases risk for both subthreshold and acute psychotic symptoms in youth

What the researchers found

Cannabis use is associated with increased risk of psychotic symptoms (both subthreshold and full), exacerbation of psychosis in vulnerable youth, and worse outcomes in established psychotic disorders. Integrated treatment addressing both cannabis and psychosis shows the most promise.

Why it matters

Cannabis use and psychosis onset both peak in adolescence and young adulthood. Understanding how they interact is critical for prevention and for treating the growing number of young people with co-occurring cannabis use and psychotic symptoms.

The numbers in context

Review covers both attenuated (subthreshold) and acute psychotic symptoms. Cannabis use increases risk for psychosis onset and worsens outcomes in those with existing psychotic disorders.

How the study worked

Narrative review of research on the overlap between cannabis use and psychosis in young people, covering risk relationships, mechanisms, and treatment approaches.

What this study cannot tell us

Narrative review without systematic methodology. Cannot provide pooled effect estimates. Covers a broad topic with varied evidence quality across subtopics.

How to read the evidence

Narrative review synthesizing a well-established body of evidence. Useful overview but without quantitative synthesis.

When this study was published

Published 2023.

The bigger picture

The cannabis-psychosis relationship is one of the most well-established and clinically important findings in cannabis research. As youth cannabis use becomes normalized, the proportion of psychosis cases attributable to cannabis may increase.

Questions still open

At what level of cannabis use does psychosis risk become clinically significant? Can interventions targeting cannabis use in high-risk youth prevent psychosis onset?

Common questions

Does cannabis cause psychosis in teenagers?

Cannabis use is an established risk factor for psychosis, and the risk appears highest in young people with genetic vulnerability or early-onset heavy use. It increases the likelihood of both subthreshold psychotic experiences and full psychotic disorders, but not everyone who uses cannabis develops psychosis.

How should cannabis use and psychosis be treated together?

The review suggests that integrated treatment approaches addressing both cannabis use and psychotic symptoms simultaneously are more effective than treating them separately. This includes incorporating substance use assessment into psychosis treatment and vice versa.

Read the original research

Cannabis and Psychosis.

Child and adolescent psychiatric clinics of North America, 32(1), 69-83

View on PubMed ↗Publisher’s paper ↗

Citation

West, Michelle L; Sharif, Shadi. (2023). Cannabis and Psychosis.. Child and adolescent psychiatric clinics of North America, 32(1), 69-83. https://doi.org/10.1016/j.chc.2022.07.004