In the Weeds: What You Need to Know About Teens and Cannabis

September 23, 2022

Marijuana and cannabis are all over the news these days. Legalization of THC products has occurred in many states across the country, and while the goal is to decriminalize a substance with history disproportionately putting people of color in prison, the end result is that cannabis products of all kinds are more widely available and can more easily end up reaching our adolescent patients. Join this conversation with Dr. Sara Polley, a triple-board certified physician and psychiatrist and the medical director at the Hazelden Betty Ford Foundation’s national substance use and mental health treatment center for adolescents and young adults, to learn about what products teenagers are using, how to effectively screen for use and most importantly, what we know about how using THC impacts the brains of teenagers in much different ways than adults.


Dr. Angela Kade Goepferd:  This is Talking Pediatrics, a clinical podcast by Children’s Minnesota, home to The Kid Experts, where the complex is our every day. Each week, we bring you intriguing stories and relevant pediatric health care information as we partner with you in the care of your patients. Our guests, data, ideas and practical tips will surprise, challenge and perhaps change how you care for kids.

Welcome to Talking Pediatrics. I’m your host, Dr. Angela Kade Goepferd. As kids head back to school this fall, one thing that many of us who care for teenagers have in mind is their new exposure to substances and how to counsel and talk to teenagers about their substance use. One of the trickier topics more recently is marijuana, including topics like how do we differentiate between multiple cannabis products that are available for use and consumption? What about the legalization of marijuana and what does this mean in terms of adolescent use? What’s the impact of cannabis on the developing brain and how can we keep up with all of the new products and jargon and things that teenagers might use or encounter on a regular basis?

Here to talk to us today about all things cannabis is Dr. Sara Polley. Dr. Polley is the medical director of the Hazelden Betty Ford Foundation’s national substance use and mental health treatment center for adolescents and young adults, and is triple-board certified in adult psychiatry, child and adolescent psychiatry, and addiction medicine. She provides not only compassionate and evidence-based care to her patients who ranges in ages from 12 to 25, but also publicly advocates for further investment and prevention and intervention. Sara, thanks for joining me today.

Dr. Sara Polley: Yeah, I’m so happy to be here.

Dr. Angela Kade Goepferd: All right. Let’s start with the word marijuana. Are we talking about marijuana, cannabis, THC? How do we differentiate our language when we’re having this conversation?

Dr. Sara Polley: Cannabinoids are kind of the overarching umbrella term to refer to both psychoactive and non-psychoactive compounds that are found within a marijuana plant. Typically, when people are talking about marijuana, they’re talking specifically about the flower, which is then what’s put in a blunt or a bowl and then smoked, but THC and other cannabinoids are available in many different forms. And so as we get into the conversation and talk a little bit about some of the ways that young people are using THC, we’ll be able to talk about different forms of cannabis or different forms of cannabinoids.

Dr. Angela Kade Goepferd: Speaking of teenagers, how common is cannabis use among teenagers? Tell us a little bit about how often they’re using it and what the trends are.

Dr. Sara Polley: By and large cannabis use has increased in young people. I don’t think that’s going to be surprising information to those of us that are with young people and see them every day. One thing that I think is really important for us to talk about though, is that the majority of teenagers do not use marijuana. And that might be really surprising because I think we hear young people talk about it, we hear it glorified a lot in the media, but when they do the national studies, like NIDA funds the Monitoring the Future study, which is kind of the gold standard in asking kids from all walks of life, eighth grade, 10th grade, 12th grade, “What are you doing with regard to health-related behaviors?” Less than 40% of adolescents are using marijuana within the past 12 months. And even less of young people are using marijuana with any regularity in a 30-day period. And the number of kids that are using marijuana daily is much less than 10%. It’s around five to 6%. So although it’s prevalent and it’s increased in prevalence within the past five years, it’s still not the most commonly used substance. Teens are much more likely to use nicotine and alcohol than they are to use marijuana.

Dr. Angela Kade Goepferd: And it reminds me of when we’re doing things like sexual health counseling with adolescents, all of them have the impression that every other person is having sex. And sometimes just giving them those numbers and helping them realize that actually less than half of your peers are having sex, or 40% or less of your peers are actually using marijuana, takes a little bit of the pressure off of them that they might not even realize they’re putting on themselves because they have a misconception about how common something is. And so what I heard you say is that daily or regular marijuana use is relatively uncommon in teenagers. It sounds like what is more common is trying or kind of sporadic use. Is that accurate?

Dr. Sara Polley: Yep. That’s exactly right.

Dr. Angela Kade Goepferd: So what types of products are adolescents using? And this might get back to our conversation about the naming conventions. Are kids smoking, vaping? Are they using edibles? What are they consuming?

Dr. Sara Polley: There’s a lot of different ways to use THC. And when I say THC, the reason I say that is because it’s the main psychoactive compound found in cannabis. And so when people are looking to get a euphoria or a high, typically they’re using THC to do that. CBD is an example of another type of cannabinoid that isn’t thought to have the same psychoactive properties as THC. And so you may hear people talking about using CBD, and when they’re doing that, they’re not achieving a higher euphoria. They’re using it for other perceived benefits, which we don’t have the research to back up, but that people read online and think that it’s helpful for.

Dr. Angela Kade Goepferd: Sure.

Dr. Sara Polley: You might also hear young people talk about delta-8, delta-10, delta… Delta-9 is THC. And there are other types of cannabinoids which do have psychoactive properties. And so that’s what they’re talking about, is that there’s these other types of cannabinoids that are within cannabis that are isolated and then are used for misuse or for purposes like that.

People are also using a lot of edibles. Particularly as edibles are becoming legalized, they’re more accessible. I think the perception of risk is a lot lower with an edible.

Dr. Angela Kade Goepferd: Sure.

Dr. Sara Polley: It seems fun which appeals to young people and can be uncommon way to use THC. And then there are concentrated forms of THC. And those are particularly worrisome when we talk a little bit about brain development and impacts to the brain. And so the names of those, sometimes people will refer to them as waxes or oils. And those are the products that are then kind of illicitly prepared into pods, which go into electronic cigarette devices and then are vaped. So that’s another way that young people are using marijuana or THC.

Dr. Angela Kade Goepferd: Let’s talk a little bit about how THC impacts the developing brain. As we were walking to record, I was talking to you a little bit about the difference between adult use of cannabis and teenage use of cannabis. Why might we be more concerned about teenage use of cannabis?

Dr. Sara Polley: Talking about a 40-year-old or a 30-year-old smoking marijuana recreationally with their friends is a really different conversation and a different topic than talking about someone between the ages of 12 and 25 using marijuana because their brain is so sensitive. And what I mean by that is that the prefrontal cortex is the last part of the brain to develop in the human. And so that process is still underway into the mid-20s. And we know that because it’s still under development, it’s actually very vulnerable to derailment by exogenous substances or stress or trauma. And so what you’re doing when you’re putting in a substance into your brain during that time period is you’re disrupting what otherwise would be the normal development of that part of your brain.

And so what we see is that young people, not only while they’re using cannabis, but even after they’ve stopped using cannabis, if their use was heavy enough, they will see changes in the way that their brain developed mimicking ADHD. Impulse control difficulty, difficulty with emotional regulation, increased prevalence and treatment resistance of their underlying mental health conditions. And so I try to educate families and let them know that really that’s a sensitive period for their brain. And you want to actually try to limit the exposure to substances in that period because you don’t want to accidentally end up with problems that you didn’t have before that time.

Dr. Angela Kade Goepferd: One of the things that I hear from teenagers in particular is that they perceive using marijuana to be a safer alternative to other substances. They’ll say things like it’s natural, it’s a plant, it’s fine for me to use it. And so what I hear you saying is, regardless of the form that it’s coming in, the psychoactive properties, or the way that it’s interacting with the brain can be problematic. Is that right?

Dr. Sara Polley: Yeah, that’s exactly right. I agree that that’s what I often hear. And even among kids who are coming in for treatment, there’s a lot who say, “Yep, opioids were for sure a problem for me. Methamphetamines, for sure a problem for me, but the marijuana, that wasn’t a problem for me.” And so what we try to educate and talk about is that all substances of abuse come with risks associated with them. And so if we were going to head-to-head compare the risks of different substances, we could rank them as to what’s the riskiest and what’s less risky, but really they’re all risks. And so let’s try to minimize your exposure to those risks, because there are things we can’t control and you’re going to be exposed to those things anyway. So let’s try to control the things we can.

Dr. Angela Kade Goepferd: Another perhaps myth that I hear is that marijuana or cannabis is not addictive, that you can’t get addicted to it. And yet when I had Dr. Joseph Lee come and give a grand rounds, he said that the number one reason that teenagers are admitted for inpatient treatment at Hazelden at the time was addiction to marijuana. So could you talk a little bit about that addiction myth and how we can maybe respond to that?

Dr. Sara Polley: The thing that makes a substance addictive is dopamine. We see an increase in dopamine in the brain when we do things that are pleasurable. And that’s why we see addiction to behaviors in addition to addiction to substances, because some behaviors also increase dopamine in our brain. And so marijuana does that, just other substances of abuse. And for each individual person, the amount of dopamine that a given substance will create is going to be different. And that’s why some people have a propensity to use or really like certain substances. And other people will try a substance and say, “I didn’t like that one.” Or, “It didn’t pleasurable to me.” And so marijuana does that just like every other substance. And so, yes, it is addictive. It’s been studied and that’s why it’s in the DSM as a diagnosis and a use disorder. Is that it comes with tolerance. It comes with withdrawal. It comes with the other symptoms that are associated with a use disorder.

Dr. Angela Kade Goepferd: One other thing that I often hear from teenagers in the office is that they are using cannabis or THC to treat a symptom that they’re aware of. So I have anxiety and I take an edible in the evening for my anxiety so I can sleep. Or I have a sleep disorder. And when I use marijuana, when I smoke before bed, then I can sleep or whatever the case may be. They perceive that the medications that I might be offering them, an anti-anxiety medication, a sleep medication are more dangerous to their health than using the marijuana that they’re using recreationally. So can we have a little bit of a conversation about how to handle those types of conversations with teenagers and even sometimes their parents?

Dr. Sara Polley: No. I like to use analogies for other medical conditions because I feel like that usually resonates with people. And so sometimes I talk about, I think that over time, I’m hopeful that we’ll be able to study marijuana and study THC and ratios of THC to CBD to be able to figure out how we as medical professionals can use it therapeutically. Because I think the approach of having it just be off limits, this is bad, isn’t going to work and isn’t fair because it could be really effective for the treatment of certain things in certain people but we just don’t have that information right now. And so sometimes I refer to it like what if you had a lump in your leg and I didn’t know what it was, but I was like, “Hey, it could be cancer so let’s do radiation and chemotherapy.” You’d be like, “Excuse me, do you want to figure out what it is? Do a treatment that’s supposed to be used for that, that comes with less risks because I think chemotherapy and radiation come with a lot of risks, they’re painful.”

So it’s the same thing with marijuana. It’s like, sure, maybe the marijuana helps you with your sleep. You do it because it helps you. I’m not going to argue with you that it’s not helpful, but why are we using this bazooka gun to treat a sleeping problem when I have well-studied FDA approved medications, where I know that the benefits are going to outweigh the risks for you and your age group? Whereas we have marijuana where we don’t even know if the benefits outweigh the risks, I have a hunch that they don’t for your age group. I think the risks are going to be more than what the benefit would be. So, yeah, it’s an important conversation to have. And really, I start those conversations most frequently with just validating. And I think all of us that work with kids are really good at doing that, where we validate their experience and what’s helpful for them, and also help them to recognize what the drawbacks might be.

Dr. Angela Kade Goepferd: Sure.

Dr. Sara Polley: Because a lot of them will be able to identify some and then use that as the start of the conversation.

Dr. Angela Kade Goepferd: We talked a little bit about CBD products earlier and there are marketed CBD products for things like sleep and relaxation. And I know there’s not good studies about efficacy of those products, but I’m wondering about harm of those products. So if we know that THC can have a prolonged impact on the developing brain between 12 and 25, does CBD have an impact? Do we know? Should we be avoiding those products as well?

Dr. Sara Polley: Yeah, well, we don’t really know. So that’s the big question. Is they haven’t been systematically studied in the age group of young people where their brains are more sensitive. And honestly, when I look at the research related to CBD, I think that there’s probably some really specific use cases that are going to come out over time as being something that CBD is helpful for. But I think a lot of the products that are marketed are kind of like snake oil, taking advantage of people who just want some relief and want some help. And so they’re kind of marketed this product.

The other piece that’s hard about CBD and why I tend to shy away from recommending it for patients is that the market is not well regulated. And so people are producing these things that they’re saying are CBD, that they’re saying don’t contain THC, but when they’ve sent those products to laboratories to test, what’s actually in this? There’s all kinds of stuff like heavy metals and fungus and all kinds of things that particularly if you’re going to vape it, you wouldn’t want that stuff to go into your lungs or into your body. So I always caution patients and parents when they’re looking at that. That maybe in the future I’d be able to help you and recommend that, but right now it’s just we don’t have enough information.

Dr. Angela Kade Goepferd: Another tricky conversation is around legalization. So there’s obviously a lot out there happening around legalization of marijuana and cannabis products. And I think some fairly good arguments from my perspective around the systemic racism behind the criminalization of marijuana and our prison system and mass incarceration. I also am aware that when things are legal, there is often a misperception that they are safe. And alcohol seems to me like a classic example of that. It’s a legal drug, but it’s certainly not safe by any means. So can we talk a little bit about the legalization of marijuana and if we know how use by adolescents is impacted by legalization?

Dr. Sara Polley: I think a misconception about those of us that work with patients that have substance use disorders is that we would somehow be against legalization, just kind of across the board. And I think it’s really important to recognize that substance use is a public health concern. We know that using criminalization isn’t an appropriate intervention for something that’s a public health concern, right?

Dr. Angela Kade Goepferd: Right.

Dr. Sara Polley: The war on drugs has been misused by the government to incarcerate people like people of color and marginalized communities. And to me, the question of legalization and whether something is legal is a completely separate kind of topic. And it’s more of a war type topic than what the impacts on a given person are from that substance.

Dr. Angela Kade Goepferd: Sure.

Dr. Sara Polley: And so I’m hopeful that with legalization will come money that’s directed towards doing education for people about what the impacts of marijuana are, how to know if you have a problem with marijuana versus if you’re using it recreationally.

Dr. Angela Kade Goepferd: Sure.

Dr. Sara Polley: Kind of like what’s happened with the tobacco industry where we’ve been able to do some more public education. We do know from research in states where marijuana’s become legal for recreational purposes, that youth use increases and a big reason for that is increased access. So if it’s just in people’s homes, then it’s more likely that a young person will find it. It’ll be easy to try and then they’ll like it and then they’ll keep doing it.

Dr. Angela Kade Goepferd: So if we know that marijuana use and cannabis use is up among adolescents, and I do think there’s a trend toward legalization. So that might mean more access in the future. How do we intervene in the primary care office? Particularly, how do we know when something is becoming problematic?

Dr. Sara Polley: There’s a lot of really good screening tools that can be used in a primary care setting. And so my favorite is something called craft. I mean, it can be administered by the clinician or self-administered, and that’s very evidence based as far as being able to determine if a patient is rising to the level of needing a referral or needing a brief intervention. And it actually includes materials on how to do a really quick brief intervention, which is a lot of just education about how a substance might impact your brain development or talking about healthy coping skills. It’s things that are easy, because I know that’s a big deal. When you have a short appointment, you need something that you can do in two minutes that you know is going to be helpful.

I would say if you have a young person coming in that has mental health concerns, that automatically puts them into a category which makes them at a higher risk of substance use. And so it would be important to screen those kids and ask questions about their use.

Coaching parents is also really important. I’m always surprised when I work with young people about how many of them don’t actually know if their parents are opposed to them smoking marijuana or not. Because I think the parent has this idea that, well, they might just experiment with it and hopefully won’t be a problem, but they’ve never actually had a direct conversation like, “In our house, marijuana is against the rules. I don’t want you smoking marijuana. And that if I find out you’re smoking, this is what we’ll do about that. These are going to be the consequences.” So coaching parents to really be clear with their kids about what the expectations are.

Dr. Angela Kade Goepferd: Just like I have parents who drink with their kids, I also have parents who use marijuana with their kids and don’t perceive it as harmful. They perceive that they’re providing a safe setting in which to share edible or smoke marijuana with their kids. And I have found that tricky because I have been concerned about what you mentioned earlier about the impact on the developing brain. And while I would not bat an eye potentially at the parent using the marijuana the way they’re describing, I’m kind of concerned about the kid. And so have you run into that or do you have tips for us for how to approach that somewhat uncomfortable conversation with parents?

Dr. Sara Polley: Yeah, I’ve actually run into that and I’ve had some pretty direct conversations with parents. I think you could use your clinical judgment. I think it might even be a good practice to just speak with the parent individually so that they’re less embarrassed about it in front of their child. And just say, “I totally get where you’re coming from with this idea and I want to tell you why I’m worried about it.” And to share impacts on brain development.

Additionally, we know that young people under the age of 18 who use any substance are at a hugely increased risk of developing addiction later in adulthood. And so explaining that to parents too, and saying really at this age, you want to try to prevent your child from using anything because you don’t want your child to develop an addiction. And so we’ve got to try to protect them in the same way that we do other safety behaviors, like get your kid to wear the seatbelt, have them wear a helmet, tell them not to get in the car with somebody who’s been drinking and call you instead. These are all safety related behaviors and this is just another example.

Dr. Angela Kade Goepferd: Sure. I think maybe the last thing I want to close with is resources for folks in primary care who are running into issues with addiction, whether it’s marijuana related or otherwise. If we suspect that a teenager has a problem, where should we go first and what resources are available to us?

Dr. Sara Polley: There’s a lot of information that’s available online that is just education related to substances, education related to, for example, what is binge drinking and what is the definition of binge drinking? The National Institute for Drug Abuse has a lot of information. They have a section that’s called facts for teens that has printable materials that you can give to parents and teens. SAMHSA [Substance Abuse and Mental Health Services Administration] also has resources. There’s tools on the SAMHSA website, where you can search by location for providers of substance use services in your area and particularly Suboxone. So if you have a teen who you’re concerned is having an opioid use issue, it gives you resources. Suboxone, that’s the brand name, but the generic is buprenorphine. It’s the treatment for opioid use disorder. So that’s another option that’s available.

We often will coach parents. If you’re in the primary care setting to reach out to their insurance and ask what would be considered in network for treatment facilities for substance use, because sometimes that can be hard to navigate knowing what’s in network and what’s out of network.

Dr. Angela Kade Goepferd: Sure.

Dr. Sara Polley: I work at Hazelden Betty Ford Foundation and we’ve got a website with a lot of different materials and multiple levels of care. That’s something that I think parents sometimes have a misconception about, is they think that the only choice is an inpatient rehab. And so then when they have a child who’s using marijuana that they’re worried about, they think, “Well, my kid doesn’t need to go to rehab. So then they don’t need treatment.” And so explaining that similarly to how you come to my office and I’m your doc and you see me, that exists for treatment of substance use too. It’s not just rehab or nothing. There’s outpatient things that can be done. Therapy appointments, a child’s school might have resources to someone that they have a partnership with that can get them in for outpatient services.

Dr. Angela Kade Goepferd: I know we’re in a bit of a mental health crisis right now when it comes to kids and adolescents. And one of the reasons for that is lack of availability of providers and services. What does it look like in the addiction world? Is it pretty easy for someone to get in for services, whether that’s inpatient or outpatient? Is there typically a long wait? What does that landscape look like?

Dr. Sara Polley: It depends what type of service you’re looking for. I think those of us that work in substance use know that when somebody has the motivation for change, we have to seize on that moment right then because people can develop ambivalence really quickly. And so I think for more significant substance use disorders, we’re really good at getting people in within the first 24 to 48 hours after their initial phone call. It is a struggle for outpatient care. I wish that it wasn’t. I wish that it was easier to access care, but I think you’ll find probably similar weights for outpatient care that you would find for outpatient mental health or therapy.

Dr. Angela Kade Goepferd: Well, Sara, thank you so much for joining us today. This was really informative conversation for me as a pediatrician, as a parent, just as a person trying to navigate these complex issues. So I appreciate you taking the time to talk with us today.

Dr. Sara Polley: Of course. Thank you so much.

Dr. Angela Kade Goepferd: Thank you for joining us for Talking Pediatrics. Come back each week for a new episode with our caregivers and experts in pediatric health. Our executive producer and showrunner is Ilze Vogel. Episodes are engineered, produced, and edited by Jake Beaver. Amy Juba is our marketing representative. For more information and additional episodes, visit us at, and to rate and review our show, please go to