It is well known in mental health circles that stimulant drugs are linked with bad behavior and mental problems when abused. Now comes a new study published in the American Journal of Psychiatry linking methamphetamine abuse with schizophrenia. The study, Methamphetamine Use and Schizophrenia: A Population-Based Cohort Study in California is notable for its sample size: over 42,000 people were examined.
The study confirmed the suspicions that many researchers had long suspected: abuse of methamphetamine is associated with severe mental illness. The study also confirmed a growing literature finding a link between marijuana and psychosis.
The study confirmed the suspicions that many researchers had long suspected: abuse of methamphetamine is associated with severe mental illness. The study also confirmed a growing literature finding a link between marijuana and psychosis.

"The study also confirmed a growing literature finding a link between marijuana and psychosis."
We can yuck it up all we like laughing at that ridiculous old propaganda film, but there really is a link between reefers and madness.