As cannabis has become more widely available and socially accepted, many adolescents and their parents view it as relatively harmless. In fact, high schoolers in 2024 perceived regular cannabis use as less risky than high schoolers in the year 2000. But how harmless is it? 

When most people think about the risks of adolescent cannabis use, they often picture impaired judgment or trouble concentrating in school. While these are real concerns with cannabis use, fewer are aware of some of the more serious (albeit rarer) risks of cannabis use, especially when used regularly. 

Today’s cannabis products often contain much higher concentrations of tetrahydrocannabinol (THC), the primary psychoactive component of cannabis, than products available even a decade ago. Higher-potency products are associated with greater risks of adverse effects. As cannabis becomes more accessible and more potent, pediatricians are seeing consequences that many families have never heard of:

Cannabinoid hyperemesis syndrome (CHS)

CHS is characterized by recurrent episodes of severe nausea, vomiting, and abdominal pain in people who use cannabis regularly. Unfortunately, because the syndrome remains unfamiliar to many families and even some healthcare providers, adolescents may undergo repeated emergency department visits, imaging studies, laboratory testing, and hospitalizations before cannabis is recognized as the underlying cause.

With severe repetitive vomiting teens are at risk for dehydration, electrolyte imbalances, temporary kidney injury, weight loss, and significant disruption to school and family life. The most effective treatment is stopping all cannabis use, however some adolescents may continue using cannabis before being diagnosed because they believe it helps relieve nausea, unknowingly worsening the cycle.

Mental health effects

Research has shown that regular cannabis use during adolescence can affect attention, memory, learning, and executive functioning—skills that are still developing during the teenage years.

Frequent use has been linked with poorer academic performance and may worsen anxiety or depression in some adolescents. In susceptible individuals, particularly those with a family history of schizophrenia, cannabis can also increase the risk of psychotic symptoms like hallucinations or of developing psychotic disorders like schizophrenia.²

Dependence.

Cannabis is not always considered to be an addictive drug, however this is a common myth. While addiction is more common in adults than adolescents, those who begin using cannabis products in their teenage years are more likely use increasing amounts of cannabis and/or develop cannabis dependence in adulthood compared to people who start using cannabis as adults. Interestingly, adolescents with ADHD are also more likely to develop cannabis dependence than their peers.²

While not every adolescent who uses cannabis will experience these complications, they are important risks that deserve greater public awareness. One reason these harms remain under-recognized is that conversations about cannabis often become polarized. Some portray it as entirely harmless, while others rely on fear-based messaging that adolescents quickly dismiss. Neither approach serves young people well.

Instead, we should communicate honestly and factually so adolescents can make more informed decisions about their health. Just as we educate families about the risks of vaping, alcohol, or prescription medication misuse, we should provide balanced information about cannabis. Legal does not mean risk-free, particularly for developing adolescents.

As pediatricians, our goal is not to stigmatize adolescents who use cannabis. It is to ensure that families have accurate information so they can make informed decisions. Too often, the first time parents learn that cannabis can cause severe illness is after their child has been admitted to the hospital.

By increasing awareness of conditions like cannabinoid hyperemesis syndrome, encouraging open conversations about substance use, and continuing to invest in research on the effects of cannabis in youth, we can help adolescents avoid preventable illness. As cannabis becomes more common in our communities, our education efforts must keep pace.

Annina Beus MD is a pediatrician in Manchester.