Cannabis users may be highly prone to suffer from psychosis.

This meta-analysis assessed whether people using cannabis (marijuana) have increased risk of suffering from psychosis. Researchers reviewed the findings of 10 studies involving more than 65,000 persons. 

Researchers noted that psychosis occurred at a high frequency among cannabis users compared to non-users. Evidence from this study support the hypothesis that the use of cannabis is associated with increased rate of occurrence of psychosis.