A systematic review and meta-analysis examined the efficacy of cannabinoids in the treatment of mental and substance use disorders. The study analyzed 54 randomized controlled trials and found that cannabinoids can reduce symptoms of some mental and substance use disorders. However, the quality of the available evidence was mostly low, which reduces the reliability of the conclusions. Based on their findings, the researchers concluded that the use of cannabinoids to treat these conditions is rarely justified. The study highlights the need for further research with a higher quality of evidence before wider clinical use of cannabinoids in psychiatry. These findings are consistent with existing knowledge about the negative effects of cannabinoids on cognitive function and mental health.