As a growing number of states legalize marijuana and public perceptions shift, more teens may feel that marijuana isn't dangerous – putting them at higher risk for marijuana use.
"Teens may think because it is legal, it is safe," says David L. Atkinson, M.D., Medical Director of the Teen Recovery Program at Children's Health℠. "Most of these teens believe in the idea that it is a medicine. They think doctors wouldn't prescribe a medicine that is harmful, but in fact medicines are harmful when used without a prescription or without doctor supervision."
Learn about the risks of marijuana use in teens and ways to talk to your child about the drug.
What are the effects of marijuana on the teenage brain?
Marijuana has toxic effects on the developing teen brain. A 2018 study showed marijuana is more damaging than alcohol to adolescent brains, leading to problems with memory and inhibiting impulses that persist after marijuana is stopped.
"Marijuana is addictive," says Dr. Atkinson. "Like any drug, how addictive it is depends on how much people use, how they get it into the brain and what age they start using."
Starting marijuana use at a young age means the drug is more addictive due to how teenage brains work. Teenage brains seek out strong sensations and are often willing to take more risks than adult brains, a combination that could lead to a higher use of drugs. Heavy marijuana use can also make teens more likely to become addicted to other substances, particularly opioids, later in life.
Heavy use of marijuana before age 16 has also been strongly correlated with the development of schizophrenia. THC, the main psychoactive substance in marijuana, can cause psychotic behavior, including hearing voices and seeing things that aren't there. Most researchers believe that marijuana use can cause permanent schizophrenia in adolescents.
Marijuana use can also cause long-term impairments to memory, especially the ability to hold multiple thoughts in your mind at once, called working memory. Researchers again believe these impairments may be permanent if adolescents are heavy marijuana users. One study showed that even 25 years after stopping marijuana use, users had a six to eight point reduction in IQ.
Finally, marijuana lowers motivation. In teens, this effect can be huge as they may miss out on opportunities that won't present themselves later in life. Missing these opportunities can have a snowball effect on a young person's life, changing what education, jobs and relationships they are able to achieve as adults.
Vaping and marijuana
With the growing popularity of vaping, marijuana can become even more accessible to teens. A new study found that nearly 1 in every 11 middle and high school students have smoked marijuana using e-cigarettes.
Dr. Atkinson warns that vaping marijuana has unique risks.
"The use of e-cigarettes to vape has enabled students to get away with using marijuana much more often and in more locations than they typically would," says Dr. Atkinson. "There's not much of a smell produced, and kids can assure anxious parents that it is just flavoring or just nicotine, not marijuana."
Dr. Atkinson warns that some vaping cartridges can be up to 90 percent pure marijuana and even CBD oil cartridges may contain THC.
"E-cigarettes also allow kids to 'microdose' marijuana all day long," says Dr. Atkinson. "They give themselves a small amount up to 30 times per day."
Vaping throughout the day, even in tiny doses, leads to heavy use among teens – putting them at risk for long-term health problems.
How parents can talk to teens about marijuana
The best way to prevent these effects on your child's long-term health is to talk to them about marijuana before they are ever exposed to the drug – as young as 10 or 12 years old. Dr. Atkinson says you should make your expectations about no drug use clear and speak openly and honestly about marijuana.
"It's important to build trust with your child," says Dr. Atkinson. "Don't exaggerate the facts. For instance, while it is addictive, not everyone gets addicted but everyone is at risk for addiction."
Dr. Atkinson says it is okay for parents not to know all the answers about drugs. If kids have questions, you can look them up together on reputable websites. Parents should also answer questions about their own past use honestly and include why they never used or stopped using, whether it was to get a job, do well in school or maintain stronger relationships.
Signs of marijuana use in teens
If you are concerned your child is using marijuana, you can look for signs of substance use such as:
- Reddened eyes
- Giddy or euphoric behavior
- Laughing inappropriately
- Drug paraphernalia like bongs, rolling papers or vape pens
- Friends using marijuana
- Common mentions of marijuana in the teen's music or conversations
While these signs may not mean that your child is definitely using marijuana, they can be a good starting point for a constructive, positive and open conversation about the harms of marijuana.
Marijuana has toxic effects on the developing teen brain. Learn about the risks and ways to talk to your child from @Childrens.
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If you are concerned about your child's drug or alcohol use, the Teen Recovery Program at Children's Health can help them improve mental health and overcome addiction.
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