Regular Cannabis Use Doubles Schizophrenia Risk

As many as one in seven cases of schizophrenia may be triggered by cannabis use, suggests new Australian research.

The study, published in the current Australian and New Zealand Journal of Psychiatry, finds that the drug causes an excess production of dopamine which can trigger psychosis. Approximately 10 to 25 percent of individuals are especially vulnerable to this happening, due to a fault in the catechol-O-methyltransferase (COMT) gene. When faulty, the gene prevents the proper breakdown of dopamine in the brain.

Overall, the study found that people who took the drug had a 40 percent increased risk of experiencing a psychotic episode. For long-term daily users, the risk increased to 200 percent. Risks also increased among those who began using cannabis at a young age.

Critics of the study have remarked that while there has been a great increase in the number of users in the past 50 years, incidence of schizophrenia has not increased.

Read more: Daily dope doubles schizophrenia use