How substance abuse can affect teen mental health

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For many teenagers struggling with mental health, substance abuse can happen simultaneously.

A national survey of teens from 2022 found those who experienced a major depressive episode were more likely to have used drugs, smoked marijuana or engaged in binge drinking.

Adults also use drugs or alcohol to cope with the symptoms of mental illness, but what does that mean for teenagers, whose brains are still developing?

Although it’s illegal to sell alcohol and cannabis to minors, more kids are getting access to drugs and alcohol through social media. Teens can find drug dealers through apps like Instagram and Snapchat, or even find out which gas stations sell alcohol to underage kids.

Kids who use alcohol and marijuana, “are impacted by those substances in a variety of ways, particularly from an emotional standpoint,” says Dr. Peter Provet, an adolescent psychologist and president and CEO of Odyssey House, a sober living and addiction treatment center in New York City.

Provet says using alcohol and marijuana impacts a child’s emotional wellbeing, particularly the development of the brain’s frontal lobe, which regulates thinking, planning, motivation and impulse control.

New research is helping scientists better understand how using marijuana as a teenager might trigger mental health issues. A 2023 Columbia University study found that 1 in 10 adolescents was using marijuana casually. That study also found that teens who use marijuana were more likely to develop psychiatric disorders, such as depression and suicidality than those who never used it.

How does marijuana affect teens’ brains? 

“The most important variable here is the THC levels, which is the active chemical in marijuana that makes people high. The THC levels in marijuana have increased dramatically over the years from something like 2% in the 1990s to well over 15%, 20% currently. So when kids are smoking marijuana today, it's not like your parents’ marijuana back in the ‘70s and ‘60s.

“It's a totally different drug, which increases all kinds of problems for kids … social isolation, low motivation, various types of brain impairment as we refer to in addition to psychosis and to some degree suicidality.

“The altered state that marijuana produces is a symptom of underlying struggle. I don't think we can say it creates social isolation directly. It creates anhedonia, the lack of emotion, etc. Kids are vulnerable in their adolescent years to this range of sort of social phenomena.”

How do parents know if their child is suffering from drug or alcohol abuse? 

“Marijuana is now understood as an addictive substance. The definition of addiction has changed over the years, where it used to be defined by dependence and withdrawal, physical symptoms of a substance. Today, the definition is much broader.

“We now talk about marijuana addiction where a kid in this case feels the need to use daily and it impacts their social world. It disrupts their social functioning. And in that, we find now the definition of addiction.

“If we suspect or we know a teen is using, say marijuana or alcohol, one of the first things we do is talk to families who come to us at Odyssey House. We talk to the families about changes in behavior.

“[In] the teen years, we see great change in the way children function. However, we try to key in to significant changes that are more abrupt, such as a kid all of a sudden losing interest in hobbies, a kid isolating suddenly much more, a kid having angry outbursts. Significant changes in behavior can alert the parent to potential drug use.”

What advice do you have for parents who have kids that are using drugs or alcohol?

“I'm always trying to help a teenager feel comfortable in their own skin. That's the biggest thing, to try to help a kid be comfortable in who they are. We know for teenagers being accepted in social groups is a key force and that can lead to drug use when a kid gets involved with the wrong group.”

What does recovery look like for a teen recovering from substance abuse? 

“The best treatment and recovery is helping the person find purpose in their life, helping the person … find reason to go forward in their life. Just stopping drugs is not the answer.

“Yes, we want to help you stop substance use. However, at the same time, we want to help someone get excited about positive things in their life, hobbies, sports, academic accomplishment, and we help children try to envision who they want to become as they get older.”