Marijuana and Psychosis

Many people who use marijuana, including teenagers, mistakenly regard this substance as a benign drug. In addition, the legalization of marijuana in many states for both medical and recreational use has increased the perception that marijuana is not harmful and is helpful to alleviate health problems.

However, a report  that was released in January commissioned by the National Academy of Sciences, Engineering and Medicine tells a very different story.  The report shows that there is evidence that heavy marijuana use, a long history of use and the age at the beginning of use may all be risk factors that can trigger a first episode of psychosis.

Studies conducted over the past ten years have shown that marijuana  use during adolescence can be a contributing factor to both triggering or worsening mental illnesses including schizophrenia. These same studies have shown that a young person with a predisposition of developing a mental illness may be more likely to use marijuana at an earlier age than other adolescents.

Dr. Michael Birnbaum, a child and adolescent psychiatrist at Northwell Heath said that we do not have a lot of research on the effects of marijuana on the developing brain of adolescents. “If pot turns on that switch,  it’s not something that can be easily turned off.  Marijuana could effectively trigger a primary psychotic disorder, meaning that even once the substance is removed, the symptoms are still there.” However, in his experience when working with young people who have mental illness, he says that “inevitably pot, and drugs and alcohol become part of the conversation.

Developing mental illness cannot be related to one thing so according to Dr. Birnbaum one cannot say that using marijuana causes schizophrenia.  However, he goes on to say  that “evidence suggests that pot smoking can lead to earlier onset (of psychosis)- that it can develop sooner that it would have otherwise.  In addition, pot is also associated with development of illness in otherwise healthy individuals, meaning it is possible that psychosis would not have developed in that person if they had never smoked pot.”

Michael Compton, MD, MPH a professor of clinical psychiatry at Columbia University has also conducted several studies considering the association between first episode psychosis and cannabis use.  The studies showed as reported by an article by Jukian Garey,  “an association between the escalation of marijuana use and an earlier age of onset of prodromal symptoms and an earlier age at onset of psychotic symptoms.”

Dr. Compton says that “These findings suggest that adolescent/premorbid marijuana use is not only a risk factor for the later development of primary psychotic disorders (which has been shown in prior studies), but is also a risk factor for an earlier onset of those disorders.”

The issue of onset is important because the long-term outlook for someone with schizophrenia is better, the later the disorder develops. Another issue of concern is that the risk of a first psychotic episode is lower if a young person uses marijuana less frequently, however, once it occurs, stopping the use of marijuana does not eliminate the mental illness.

As Dr Brinbaum observed, “If pot turns on that switch,  it’s not something that can be easily turned off.  Marijuana could effectively trigger a primary psychotic disorder, meaning that even once the substance is removed, the symptoms are still there.”

Dr. Birnbaum suggests that it is impossible to tell what risk a teenager is taking by smoking marijuana on a regular basis.  He goes onto say that if an adolescent has hallucinations or other psychotic-like experiences while using, that is an indicator that they may have a predisposition to some kind of psychotic illness. In this situation, it would be prudent for that teen to avoid substances.

It is important for parents to share this latest research with their children. Let them know that using marijuana could be setting them up for trouble. And that scientists do not know enough about the risks of marijuana to the developing brain. Starting to use marijuana at a young age increases the risk of dependency which negatively impacts a young person’s ability to perform well in school and have meaningful relationships.

Source: Parenting for Prevention, Patricia M Warble, LCSW, CPC