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Cannabis Risks

What You Need to Know About Teenagers and Cannabis   

Learn the cannabis basics and how cannabis affects the developing brain. Your teen may not be aware that getting high can hurt their growth. Let them know with a few key facts. Also, take a moment to discover how the chemicals in cannabis can impact a teenager’s mental health. But to kick things off, learn who’s using cannabis and where. 

Are Teens Using Cannabis in California?

The answer is, yes. In California, many teens are using cannabis (PDF). If your teen hasn’t been exposed to it already, they most likely will be. That’s why talking with your teen about it now is so important. Even if it feels like they’re not listening, keep trying. Every conversation makes a difference. 

Who’s Using Cannabis?

  • 16% of 11th graders currently use cannabis [1]

  • Cannabis use is more common than either binge drinking or smoking [1]


The Risks of Underage Cannabis Use

Teens may think they’re invincible but using cannabis can affect their brain development and health.  

Substances like cannabis can negatively affect the teen body in many ways. Research shows that cannabis may: 


  • ​​Impair learning, memory, attention, decision-making, and motivation, which can affect school performance [2]

  • Increase the risk of chronic cough, bronchitis, and asthma severity [4] 
  • ​Increase the risk of schizophrenia or other psychotic disorders in adulthood, with the highest risk among those who begin using at a young age, especially among individuals who may already be at risk because of genetics [2] 

Is it Safe for Teens to Use Cannabis?  

When talking with your teen, let them know it isn’t safe for them to use cannabis in any kind of way. Give them the information and make it one of many conversations. 

How Does Cannabis Affect the Teen Brain? 

What your teen may not realize is that their brain hasn’t finished developing yet. In fact, it’ll continue growing up until they reach their mid-20s. Using cannabis during these years can prevent the brain from working the way it should. 

What Is Tetrahydrocannabinol (THC)?

THC is an active chemical found in cannabis, and when it enters the brain, it can disrupt how the brain and body function. 

THC is believed to affect the teen brain in the following ways:

  • Problems with memory, learning, thinking clearly, and problem-solving [2] 

  • Poor school performance that jeopardizes professional and social achievements, and life satisfaction [2] 

  • Impaired coordination and reaction time 

  • Increased risk of mental health problems like depression, anxiety, and psychosis [2][3] 

How Can Cannabis Impact a Teen’s Mental Health?

Your teen may hear that cannabis is a good way to cope with stress, but  using cannabis in your teens can make stress and anxiety harder to manage. 

Frequent Teen Cannabis Use Has Been Linked to: 

Parent and Son

  • A risk for later psychotic disorders in adulthood
  • Dependency and addiction for those who use cannabis to cope with negative emotions


  • Adolescent cannabis exposure and use are associated with [2][3][6]

    •  A risk for later psychotic disorders in adulthood  

    • Dependency and addiction for those who use cannabis to cope with negative emotions 

  • THC has been shown to affect the part of the brain responsible for emotional regulation, making it harder for teens to manage stress and anxiety [2]  

  • High amounts of cannabis use can affect tolerance levels making those less sensitive to THC, meaning more THC is needed to feel the same effects [5]   

What Are Ways to Start a Cannabis Conversation?

Teens are naturally curious. When talking with your teenager about weed, try to make it a learning experience. Keep the conversation light and answer any questions as best as you can. Don’t stop at one conversation. It’s good to talk about cannabis on a regular basis. We’ve put together some ideas for getting the conversation started. Take a look! 

  • Talk Early and Often 

  • Be Casual but Clear 

  • Be Open, And Listen Without Judgment 

  • Keep it Grounded and Fact-Based 

  • If You Suspect Your Child is Using, Don’t Panic 

  • Let them know you care and are always there for them 

  • Help them say “no” ​​


[1] Austin G, Hanson T, Zhang G, Zheng C. School climate and student engagement and well-being in ... - calschls. School Climate and Student Engagement and Well-being in California, 2017/19 (PDF). ( Accessed December 29, 2022. 

[2] Surgeon General's Advisory: Marijuana use & the developing brain. ( Published August 13, 2021. Accessed December 29, 2022. 

[3] Key Substance Use and Mental Health Indicators in the United States: Results from the 2020 National Survey on Drug Use and Health (PDF). ( Published October 2021. Accessed December 29, 2022. 

[4] Tetrault JM, Crothers K, Moore BA, Mehra R, Concato J, Fiellin DA. Effects of marijuana smoking on pulmonary function and respiratory complications: a systematic review. Arch Intern Med. 2007;167(3):221-228. doi:10.1001/archinte.167.3.221

[5] Colizzi M, Bhattacharyya S. Cannabis use and the development of tolerance: A systematic review of human evidence. Neuroscience & Biobehavioral Reviews. ( Published July 26, 2018. Accessed December 29, 2022. 

[6]  Bloomfield, M., Ashok, A., Volkow, N. et al. The effects of Δ9-tetrahydrocannabinol on the dopamine system. Nature 539, 369–377 (2016).

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