Effects of Cannabis Usage
Psychosis
Cannabis-induced psychotic disorder is diagnosed when hallucinations or delusions develop during or soon after ingestion of cannabis and the psychotic symptoms are a major feature of the intoxication.
These psychotic effects can include paranoid delusions and hallucinations. People will experience effects differently.
These symptoms are often associated with heavy cannabis use or use of high potency THC products.
Schizophrenia
Schizophrenia is a serious mental illness that affects how a person thinks, feels, and behaves. People with schizophrenia may seem like they have lost touch with reality, which can be distressing for them and for their family and friends.
The NIH stated that “those who had tried cannabis by age 18 were 2.4 times more likely to be diagnosed with schizophrenia than those who had not and the risk of this diagnosis increased with the frequency of cannabis use.”
Learn More
Dr. Libby Stuyt: NMI Lecture: "Mental Health Implications of Marijuana" (60 minute video) - Dr. Libby Stuyt - 9/7/23
High-potency marijuana highlights the risk of cannabis-induced psychiatric disorders – NBC News - Akshay Syal, M.D., Kate Snow and Patrick Martin – 4/24/2024
I am a doctor. I see the harm high-potency THC does to children. - Karen Randall – Colorado Newsline – 4/16/21
Research
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JAMA Study: Cannabis Use in Teens Linked to Increased Psychosis Symptoms
“This cohort study of 11 868 adolescents found that adolescents who used cannabis at any point during the study period reported a greater number of psychosis spectrum symptoms and more distress from symptoms relative to those who never used cannabis, providing evidence for shared vulnerability.” -
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Cannabis Use and the Developing Brain: Highs and Lows
“Exposure to THC during important periods of brain development, particularly in the womb or during the teenage years, can cause long-lasting changes to the brains and behaviors of children—both in childhood and beyond.”
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The Problem with the Current High Potency THC Marijuana from the Perspective of an Addiction Psychiatrist
“Marijuana use is also correlated with creating or worsening many mental health problems including anxiety, depression, psychosis, and suicidal ideation.”
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Balancing risks and benefits of cannabis use: umbrella review of meta-analyses of randomised controlled trials and observational studies
“Cannabis use should be avoided in adolescents and young adults (when neurodevelopment is still occurring), when most mental health disorders have onset and cognition is paramount for optimising academic performance and learning.”
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Cannabis use and the risk of developing a psychotic disorder
There is now reasonable evidence from longitudinal studies that regular cannabis use predicts an increased risk of schizophrenia and of reporting psychotic symptoms. These relationships have persisted after controlling for confounding variables such as personal characteristics and other drug use.
