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Marijuana and Your Teenager: Risky Business?

by Jon Cohan, CADC

Jon is co-host of the Right Mind Media Podcast and practices individual and family addiction counseling in Concord MA. His website is

        There’s a new legal landscape in Massachusetts (and indeed much of the U.S.) in regards to marijuana, and along with it a great deal of confusing and sometimes conflicting information. America has a long and complicated history with cannabis and it doesn’t look like that will be changing anytime soon. Often presented as a benign “natural” substance, pot’s advocates claim it doesn’t carry the health risks of alcohol or the physically addictive dangers and associated negative behaviors of harder drugs like opiates or cocaine. In the media and across popular culture, marijuana use has been normalized, so much so that a recent federal study found 60% of high school students said they think cannabis is “safe”, 23% say they’ve used it in the last month, and 6% claim they use it daily. That’s three times the number of daily smokers at the beginning of this century. In our own families, many teenagers grow up knowing that while their parents may have a stern attitude about “harder” drugs, they have a relaxed outlook about weed. It’s not unusual for some teens to see their parents smoking pot to unwind after a long workday.

        In my counseling practice, I frequently work with adolescents who have experienced difficulties in social functioning, problems at school, impairment in cognitive performance, legal issues, de-motivation, and mood and thought disorders tied to their marijuana use. They often come to me endorsing the drug, claiming that it’s “natural”, “organic”, and a miracle cure for everything from cancer to diabetes. Instead of judging or demonizing their cannabis use, I try to meet them on level ground. I’m acutely aware that getting high fulfills some important need for them and they are going to guard their use closely, because, despite the negative effects it may have on their lives, it has become an important coping tool during their tumultuous teenage years.

        So, what do we actually know about marijuana’s effect on adolescents and how do we separate the hype and myth from the truth? In general, moderate pot use by adults can be a somewhat innocuous venture, but the same cannot be said about adolescents. Thanks to recent research and neural imaging, we now know that adolescents are particularly vulnerable to psychoactive substances, and their brains may be permanently and negatively altered by even casual marijuana use. Despite the recent popular narrative, there are some significant risks for the teenage pot smoker. We now know that moderate to heavy users lose an average of eight IQ points compared to those who don’t use cannabis. If there is regular weekly use before age 17, smokers have a 1.6 – 2 times greater chance of not completing high school and not enrolling in higher education. Weekly teenage smokers over time are less employed and report lower life satisfaction than their non-using counterparts. A recent study found that users who started before age 15 have 3.5 times greater risk of developing depression and anxiety and regular users also have an increased risk for lasting cognitive impairment including attention and verbal IQ deficits and executive functioning issues.

        There’s also the important issue of modern weed’s greatly increased strength: the amount of THC (delta-9-tetrahydrocanabinol, the main psychoactive ingredient in marijuana) in the average cannabis product has gone from 3.5% in the mid 90s to over 15% today, an almost fivefold increase. More alarmingly, many products, such as edibles or hash oil have a much higher percentage (up to 99%) of THC. In other words, this is not your grandfather’s marijuana. As for it being a “natural” product, the great majority of today’s cannabis products are derived from heavily genetically modified plants treated with pesticides.

Raging Change

        Teenagers are a marvel of evolutionary design, both physically and cognitively. During adolescence, the teen brain is busy making and discarding neural connections, learning faster than it ever will, but despite what they might say, teenagers are not playing with a full deck brain-wise. Major parts of a completely developed adult brain are undeveloped in the adolescent version, most importantly the frontal cortex, which is associated with logical thought, impulse control, risk assessment, and planning appropriate responses to stimuli. Instead, teen behaviors are often ruled by the part of the brain called the amygdala, which helps to govern emotions, survival, and pleasure. Because of this deficit in development some of the classic “symptoms” of the teen personality are moodiness, impulsivity, irrational reasoning, oppositional behavior, and a powerful libido (sound familiar?). So, it stands to reason that teens, by design, are going to take greater risks and be more impulsive when it comes to drugs.

        Against this backdrop of raging change, it then makes sense that introducing a mind and mood-altering substance could impact emotional and cognitive development. Combine easier access (many of my clients have told me it’s simpler for them to buy weed than alcohol) and a generally relaxed social attitude towards pot and you have the potential for misuse.

Medicating Themselves

        The claim I hear most often from my adolescent clients is that pot is the only thing that’s ever worked in easing their anxiety/stress/depression. There is some truth to their assertions of anxiety relief: studies have found that cannabinoids, the active ingredients in marijuana (differing from endocannabinoids which occur naturally in our bodies) may play a role in lowering anxiety, but only for short periods of time. It turns out that regular use can actually increase anxiety especially in teens with pronounced anxiety disorders.

        It makes sense that a 14-year-old who gets some relief from their anxiety when they first smoke marijuana would see it as the “cure” for their stress and adopt it as their go-to method of self-medication. The problem is of course that there may be a price to pay on the other end. Any teen who suffers from an anxiety disorder has a higher likelihood of developing a serious substance use disorder. Likewise, research shows that repeated use of cannabis increases the risk of developing other drug and alcohol use disorders. Cannabis is also a strong demotivator and can, among other things, potentially trigger psychosis or worsen thought disorders such as schizophrenia in those with a genetic predisposition. Research had found that adolescents with cannabis dependence have two times greater rates of psychotic symptoms.

        Of course, there are many safer, more effective ways to moderate anxiety and depression that are easily accessible to everyone; getting regular exercise, meditation using an app like Headspace or Insight Timer, limiting screen time and access to gaming and social media, cutting caffeine and nicotine intake, and regulating sleep all help to lower stress and tension. Remember, our children look to us to model healthy coping skills so we need to practice what we preach.

Starting a Discussion

        Parents often ask me when they should start talking to their children about substance use. My answer is to start the conversation early; a pre-emptive discussion about drugs and alcohol with your tween is a great step in the right direction. Kids are already learning about addiction in elementary school in Massachusetts and they need guidance from their families to navigate and process some of the conflicting messages they are receiving from the media and their peers. If they ask questions about drugs, answer them. Ignoring or discouraging discussion about drugs serves to condone their use. If your kids don’t know where you stand on substance use they can take your silence as a winking endorsement. Research shows that parent’s opinions about drugs make an impression on their children. Most importantly, if you’re worried your teenager is developing a problem with marijuana, talk to a professional about your options for getting them help.


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