Huh?
https://www.drugpolicy.org/does-marijuana-negatively-impact-mental-health
This is why we see so many studies that confirm most people diagnosed with severe mental illness have a history of alcohol and/or drug use. The alcohol and drug use was not the causeof the mental illness, however, but rather a behavior that coincides with the undetected development of mental health symptoms.
Research suggests that those with mental illness might actually be self-medicating with marijuana – turning to the plant to help manage their symptoms, rather than becoming ill after use.
Emerging evidence indicates that psychiatric patients who try marijuana show significant improvements in symptoms and clinical outcomes (such as lower mortality rates and better cognitive functioning) compared with those who have not.
And some of the unique chemicals in marijuana, such as cannabidiol (CBD), seem to have antipsychotic properties. Now, researchers are investigating it as a possible treatment for schizophrenia and depression.