Mental Health

Marijuana, mental health and the teenage brain

June 26, 2018

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By Joe Thoits, M.D., Unity Center for Behavioral Health 

Marijuana use among teens is more prevalent than ever in this country, thanks largely to the growing number of states legalizing its use for medicinal and recreational purposes.  Marijuana was legalized in Oregon in 2015, raising the profile and availability of this sometimes-controversial substance.  Regardless of how one feels about whether marijuana should be legal, it is incumbent upon all of us, and especially parents and caregivers, to understand the potential harmful effects marijuana can have on the mental health and well-being of our youth. 

Marijuana is the most widely used illicit substance on the planet, and the rise in its use among adolescents in this country over the last decade is clear.  As a child psychiatrist at Unity Center for Behavioral Health, the largest inpatient adolescent psychiatric unit in Oregon, I frequently see patients who are admitted to our hospital with anxiety disorders, depressive disorders or psychotic illness in the context of regular marijuana use.  

While it is sometimes unclear which came first, the substance use or the mental health problems, the scientific evidence is clear: regular marijuana use can lead to dependency, and it increases the risk of developing an anxiety, depressive or psychotic disorder.  The increased psychosis risk is especially true for individuals with a family history of psychotic illness. 

At Unity, we regularly work with teens who resort to regular marijuana use because they believe it will help improve their sleep, boost mood and reduce anxiety, and in the short term they may indeed experience some relief. 

What teens generally fail to appreciate is that they may make their symptoms worse over time with consistent marijuana use. Regular marijuana use, especially at a young age, has been linked to longer term negative mental effects and even reduced intelligence.  Sometimes in the case of psychosis, a teenager’s symptoms may disappear entirely with abstinence.  I know, because we see it firsthand and not infrequently.  

We talk about the adolescent brain as a brain under construction, and, therefore, particularly vulnerable to all experiences, including psychological, emotional and physiological.  

Here are five things you should know when talking about marijuana use and how it can negatively impact your child’s mental health.
Marijuana and teens
Marijuana is harmless. False
Brain changes are occurring throughout adolescence and well into early adulthood. Disruptions in brain development related to the toxic effects of regular marijuana use could significantly impact everything from academic functioning to social and occupational functioning later in life.
It matters how old you are when you start using marijuana: True
Early and more frequent marijuana use has also been associated with poorer outcome.
Marijuana helps anxious teens relax. False
There may be short-term benefits perceived by teenagers who use pot, but with frequent long-term use, especially in those younger than 18, there may be cognitive or intellectual effects as well as impacts to critical thinking skills. On average, it is safe to say that adolescents who partake heavily of cannabis wind up achieving less in life and are unhappier.
Marijuana is good for your mental health. False
Regular marijuana use can have subtle but clear negative impacts on everything from appetite to sleep, memory, learning and emotion.
Talking to your teens about marijuana will send the wrong message. False
Educate your teen about the facts and what using pot can do to their state of mind and their health both in the short-term and long term.
For media inquiries contact: Kristin Whitney.

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