Does marijuana use increase the risk of developing schizophrenia?

Updated: Mar 16, 2018
  • Author: Frances R Frankenburg, MD; Chief Editor: Glen L Xiong, MD  more...
  • Print
Answer

A new study suggests that heavy marijuana use in teenagers aged 15–17 years may hasten the onset of psychosis in those at high risk for developing a psychotic disorder. In an analysis of 247 hospitalized patients who had experienced first-episode psychosis, the Allied Cohort on the Early course of Schizophrenia (ACES) II project found that the onset of psychosis in those who used cannabis from age 15 to 17 years occurred at a mean age of 21.07 years, compared with a mean age of 23.86 years in patients who did not use cannabis during those same teenage years. However, the researchers could not say whether marijuana use may actually cause psychosis to develop early or whether people who have a predilection for earlier onset of psychosis also may be more likely, owing to various factors, to use marijuana. [51]


Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!