Yes, although it is complex. Cannabis use is one factor that has been associated with an increased risk of developing a psychotic disorder. Usually, it is a mix of frequent, heavy cannabis use, especially in adolescence, and a and a history of mental illness in one’s family that is considered the riskiest combination.
According to Health Canada, the risk with use varies from 2.5-10 % depending on factors such as family history of mental illness, age at which cannabis use starts and THC content of the cannabis.
Specifically, regular cannabis use in adolescence:
- is linked the development of a long-term psychotic disorder in at-risk individuals.
- is associated with an earlier age of onset of psychosis.
- can complicate and/or prevent recovery in individuals already diagnosed with a psychotic disorder.
For a more in-depth overview of the research, please see Health Canada’s review the literature here. A recent “review of reviews” is also available here and finds that:
“The scientific literature indicates that psychotic illness arises more frequently in cannabis users compared to non-users, cannabis use is associated with a dose-dependent risk of developing psychotic illness, and cannabis users have an earlier onset of psychotic illness compared to non-users. Cannabis use was also associated with increased relapse rates, more hospitalizations and pronounced positive symptoms in psychotic patients.”