LoginIs there evidence linking marijuana use to psychosis?
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Yes.
Peer-reviewed research found links between marijuana use and psychosis β the loss of contact with reality, experienced as delusions or hallucinations.
The consensus is there is a clear association, but more research is needed to determine ifΒ there is causation.
Thatβs according to the Journal of Cannabis Research editor, researchers at the Institute of Cannabis Research and a review of 32 studies that reviewed research.Β
The instituteβs Jeff Smith said most cannabis users donβt develop psychosis.
Research samples:
Lifetime use is associated with increased odds of psychosis, especially among daily or weekly users.Β
Psychotic disorders are 11 times more likely among adolescent users than non-users.
Republican U.S. Rep. Tom Tiffany, who represents most of northern Wisconsin, called for more research on the link to inform legalization policy.Β
Marijuana for recreational use is legal in 24 states. In May, Republicans nixed a Wisconsin legalization proposal.
This fact brief is responsive to conversations such as this one.
Sources
- National Institute of Mental Health: Understanding Psychosis
- Dr. David Gorelick, University of Maryland psychiatry professor and Journal of Cannabis Research editor-in-chief: Interview
- Institute of Cannabis Research at Colorado State University Pueblo: director and chemistry professor Chad Kinney; and strategic partnership and outreach specialist and biology professor Jeff Smith: Interview
- Psychiatry Research journal: A systematic evidence map of the association between cannabis use and psychosis-related outcomes across the psychosis continuum: An umbrella review of systematic reviews and meta-analyses
- Psychological Medicine journal: The impact of schizophrenia genetic load and heavy cannabis use on the risk of psychotic disorder in the EU-GEI case-control and UK Biobank studies
- Psychological Medicine journal: Age-dependent association of cannabis use with risk of psychotic disorder
- Scientific American: The Link between Cannabis and Psychosis in Teens Is Real
- YouTube: Congressman Tom Tiffany Joins DrydenWire Live
- CoverCannabis.com: Marijuana Laws by State for 2025. Where is Marijuana Legal?
- Associated Press: Wisconsin Republicans kill marijuana legalization and tax increases for millionaires
Is there evidence linking marijuana use to psychosis? is a post from Wisconsin Watch, a non-profit investigative news site covering Wisconsin since 2009. Please consider making a contribution to support our journalism.
