Marijuana (Cannabinoids)Psychosis

Effect of cannabis on the onset of psychosis

Researchers from Spain and Boston studied the relationship between age and cannabis use in patients with a first psychotic episode.

First, the details.

  • 131 consenting patients (age 15 to 65 years) with a first psychotic episode requiring inpatient psychiatric treatment were interviewed.

And, the results.

  • Increasing use of marijuana was significantly associated with a reduction in the age at onset of the first psychotic episode.
  • The effect of cannabis use on the age at onset could not be explained by the use of other drugs or by gender.
  • The finding was similar in the youngest patients, suggesting that this effect was not due to chance.

The bottom line?
The authors concluded, “These results point to cannabis as a dangerous drug in young people at risk of developing psychosis.”

8/7/08 21:34 JR

Hi, I’m JR

John Russo, Jr., PharmD, is president of The MedCom Resource, Inc. Previously, he was senior vice president of medical communications at, a complementary and alternative medicine website.