Ask the Expert

What You Need to Know about Cannabis Use in Adolescence

By August 30, 2018 No Comments

The decriminalization and legalization of cannabis in Canada should be a concern for parents of adolescents and young adults. Cannabis, like alcohol, is not a benign substance and it is important to recognize that the legalization of cannabis does not mean that it is safe for everyone to consume, especially for adolescents whose brains are not yet fully developed.

In fact, an adolescent’s brain is quite vulnerable. A position paper from the Canadian Pediatric Society entitled Cannabis and Canada’s Children and Youth outlined the risks of young people using cannabis regularly. The paper’s lead author Dr. Christina Grant, who is an adolescent medicine specialist in the department of pediatrics at McMaster University, emphasizes that “youth should not use cannabis recreationally because its many potentially harmful effects are serious.”

Terms Associated with Marijuana

First off, some definitions are helpful to understand the concerns. “Cannabis” refers to the psychoactive components of a plant called Cannabis sativa, which are: the dried, crushed leaves and flower buds (marijuana), the resin or sticky solid substance from flower buds (hashish), and the oils and wax (cannabis extracts). Cannabis can therefore be inhaled or ingested, depending on what form it is in. For adolescents, the main concern is THC, which is a component of cannabis that is responsible for the “high”.

Health Risks Associated with THC

This chemical causes measurable changes in the developing brain of adolescents, which can lead to lasting deficits. Specifically, THC causes toxic changes to brain cells called neurons. When reviewing scientific studies utilizing MRI scans, there are documented indications of structural changes to the brain of youth who regularly use cannabis. These studies show reduced brain volumes and thinning of the cortex or lining of the brain, among other changes.

Regular Use and Long Term Effects

Even more alarming is what we clinically see in adolescents who use cannabis regularly. One in six develop an addiction issue called “cannabis use disorder”, which can affect the ability to function in life, such that their school performance decreases and conflicts occur with friends and family. There is also a definite association between cannabis use and depression, as well as anxiety disorders.

Further, studies indicate that cannabis may have a causal relationship with the onset of psychotic disorders, particularly in those with a personal or family history of psychosis. Therefore, a major concern is the association between cannabis and such psychotic disorders as schizophrenia, which is a severe lifelong mental illness. In some instances, cannabis can immediately induce psychotic symptoms such as hallucinations and paranoia, which shows its powerful effects on the brain. For some people, these psychotic symptoms can persist for days after the use of cannabis and for others, the symptoms do not go away.

Practising emergency physicians are seeing an increase in cases of young people with a syndrome called “hyperemesis cannabinoid”, which is a condition where chronic use of cannabis causes repeated painful and debilitating episodes of abdominal pain and vomiting, often requiring them to go to the emergency room for relief. The episodes go away when cannabis use is stopped, but these individuals must refrain from any use in the future or the syndrome will return. Again, this indicates that cannabis is not a drug without its share of serious side effects and problems, and we should approach it with these factors in mind.

The takeaway message is that adolescents who are already at risk for addiction, mood or psychotic disorders should be particularly discouraged to use a substance that may significantly increase their risk of developing mental illness issues. However, most experts in the field believe that adolescents should avoid regular cannabis use, ideally until the brain fully matures at around age 24.

For more valuable health information, visit our Ask the Expert section.