Teen Cannabis Use Doubles Psychosis, Bipolar Risk

A large new study connecting adolescent cannabis use to serious psychiatric conditions is a reminder of why dual diagnosis treatment to address substance use and mental health together, matters so much for young people. As we reported earlier, teens who used cannabis had roughly double the risk of later developing psychosis and bipolar disorders.

The work was carried out by researchers from Kaiser Permanente, the Public Health Institute, UC San Francisco, and USC, with funding from the National Institute on Drug Abuse. Many of the researchers were based out in California, which already offers over a thousand programs to treat substance misuse, but the findings are applicable for young people across the nation.

The Finding for Teens

The study tracked almost 464,000 adolescents and young adults from 13 to 26. Teens who reported using cannabis in 2025 faced significantly higher risks of developing psychotic and bipolar disorders later on in life. The risk of both psychotic and bipolar disorders was approximately doubled; other conditions like depression and anxiety had elevated risks, but not as high as the others.

Broadening the picture, the study matches other researchers’ work that indicates how young people try to cope with mental health conditions. Some turn to AI chatbots for guidance, while others in isolation turn to self-harm. The statistics reflect the shortage of mental health providers in the U.S.

It’s important to be precise about what this shows. As an observational study, it demonstrates a strong association, not proof that cannabis directly causes these conditions. Timing played a critical role; on average, cannabis use was reported 1.7 to 2.3 years before a psychiatric diagnosis. The risk held even when researchers considered prior mental health conditions and other drug use.

The Mental Health and Addiction Connection

Substance use and mental illness frequently travel together, which is the core reason behavioral health providers treat them as linked rather than separate problems. Some teens even use drugs to cope with mental health disorders, but this approach rarely works.

In general, cannabis is the most commonly used illicit drug among adolescents, and products have grown far stronger. The average THC in California cannabis now exceeds 20%, and some concentrates go as high as 95%. Higher potency is part of why researchers urge that clinicians and policymakers treat adolescent cannabis as a serious health issue.

Treating a Dual Diagnosis

Co-occurring disorders, also called dual diagnosis, describe a substance use disorder alongside a mental health condition such as depression, anxiety, bipolar disorder, or a psychotic disorder. Integrated treatment matters because treating only one side tends to leave the other to undermine recovery. Care that addresses both at once produces better outcomes.

Comprehensive care can take place in residential or outpatient settings and typically blends evidence-based therapies with medication management. Clinicians widely use behavioral therapy, and a psychiatrist may manage medications. 

The study’s authors also flagged an equity concern: cannabis use was more common among teens on Medicaid and public insurance programs and those in disadvantaged neighborhoods, so access to affordable behavioral health treatment is part of the response.

Starting Care, Anywhere

If a young person in your life is using cannabis and struggling with mood, anxiety, or thinking, look for programs that treat both together. Search mental health treatment facilities and dual diagnosis treatment programs, and confirm they treat adolescents and accept your insurance. 

Call 800-908-4823 (Sponsored) for comprehensive mental health and addiction treatment or browse our directory for centers across the country.

Author

Nikki Wisher, BA

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Nikki Wisher is an Atlanta-based content writer who specializes in health and wellness. After earning her BA in English, she has been writing in the health and wellness space for over a decade, with credits ranging from addiction recovery to fitness to aesthetics and skin care. This includes her inclusive running blog forallrunners.com.

Editor

Peter Lee, PhD

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Peter W.Y. Lee is a writer and historian of American history during the Cold War. His primary focus is the relationship between youth and popular culture and its impact on U.S. society during the twentieth century. He has published widely on how the public has used popular culture as a mechanism to address political and social shifts throughout time