The hidden mental health danger in today’s high-THC cannabis
Date:
August 12, 2025
Source:
Canadian Medical Association Journal
Summary:
THC levels in cannabis have soared in recent years, raising the risk of psychosis—especially in young, frequent users. Studies reveal a strong connection between cannabis-induced psychosis and schizophrenia, making early cessation and treatment essential.
Stronger cannabis is driving higher psychosis risks, especially in young, frequent users, making quitting and treatment more important than ever. Credit: Shutterstock
“Cannabis from the 2000s is not the same as in 2025,” said coauthor Dr. Nicholas Fabiano, MD, resident and researcher with the Department of Psychiatry, University of Ottawa, Ottawa, Ontario. “THC content has increased by 5 times. This is likely a significant driver in the increasing link between cannabis use and schizophrenia.”
the last 20 years in Canada from about 4% to 20% in most legal dried cannabis.
High-potency and regular cannabis use is linked to increased risk of psychosis — The risk of psychosis is increased in people using high-potency THC (more than 10% THC), people using it frequently, and those who are younger and male. A history of mental disorders (depression, anxiety, etc.) also appears to increase the risk.
Cannabis-induced psychosis and cannabis use disorder increase the risk of schizophrenia — A recent study of 9.8 million people in Ontario found a 14.3-fold higher risk of developing a schizophrenia-spectrum disorder in people visiting the emergency department for cannabis use and a 241.6-fold higher risk from visits for cannabis-induced psychosis.
Treatment requires stopping cannabis and taking medication — Continued use of cannabis after a first episode of cannabis-induced psychosis is linked to greater risk of returning symptoms. Antipsychotic medication can help people with severe and prolonged symptoms.
Behavioral options may help with cannabis cessation — Motivational interviewing or cognitive behavioral therapy by a physician or psychologist can help build skills to resist cravings and follow treatment recommendations.
“Cannabis from the 2000s is not the same as in 2025,” said coauthor Dr. Nicholas Fabiano, MD, resident and researcher with the Department of Psychiatry, University of Ottawa, Ottawa, Ontario. “THC content has increased by 5 times. This is likely a significant driver in the increasing link between cannabis use and schizophrenia.”
Canadian Medical Association Journal. "The hidden mental health danger in today’s high-THC cannabis." ScienceDaily. ScienceDaily, 12 August 2025. <www.sciencedaily.com/releases/2025/08/250811104237.htm>.
Canadian Medical Association Journal. (2025, August 12). The hidden mental health danger in today’s high-THC cannabis. ScienceDaily. Retrieved August 12, 2025 from www.sciencedaily.com/releases/2025/08/250811104237.htm
Canadian Medical Association Journal. "The hidden mental health danger in today’s high-THC cannabis." ScienceDaily. www.sciencedaily.com/releases/2025/08/250811104237.htm (accessed August 12, 2025).
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