Three reasons to avoid a low minimum age for pot use

Young people’s health must be priority of legalization bill, says Dr. Gail Beck.

Every day in the Youth Program at The Royal, my colleagues and I see young people whose mental illnesses are complicated by the use and abuse of cannabis or a dependence on this drug. We provide these young people and their families with information on the impact of marijuana on the developing brain. We are often able to convince young people to decrease their marijuana consumption and, in many cases, to stop altogether.

Unfortunately, legislators may not be as aware of the risks of cannabis on the developing brain as mental health professionals are.

There are three categories of concern:

First, there is good evidence that marijuana use can have an impact on the developing brain. The brain continues to develop into a person’s mid-20s. Physicians and other health professionals had hoped that the legal age for marijuana use might be 25, to reduce these impacts. Most of us realize that marijuana use can impair concentration and cause a deterioration in such cognitive tasks as remembering, problem-solving and decision-making. These effects will reverse in adults a few weeks after discontinuing marijuana. In youth under 25, this is not the case.

Very often, these difficulties persist, resulting in longterm functional deterioration. Young people may even find their academic achievement deteriorates, at a time in their lives when they can least manage this. From the age of 18 until age 25, the age when brain development is completed, a young person is finishing high school, beginning post-secondary education and starting a career. Most of us call upon all our mental resources during this period and we don’t need cannabis clouding our judgment — either for a few months or in the long run.

A second concern is related specifically to the development of mental illnesses, particularly psychotic illnesses. Research evidence has demonstrated a correlation between marijuana use and the onset of anxiety disorders, symptoms of depression and psychotic disorders in youth with a predisposition to these conditions because of family history. Mental health symptoms are also a concern in acute, toxic dose-related episodes of intoxication. These symptoms include anxiety and depression, but also paranoia and brief psychotic episodes.

In the Youth Psychiatry Program at The Royal, we educate our young patients and their families about this research. We have found that this is necessary since many Canadians believe that marijuana is relatively harmless compared to other substances or alcohol. This is why both public health and mental health professionals have requested that a robust education plan accompany the implementation of marijuana legislation.

Finally, we must remember that, even when they are not intoxicated, youth — especially young men — are implicated in more motor vehicle accidents than any other age group. Marijuana intoxication is every bit as dangerous as any other intoxication and has been linked to an increased rate of traffic accidents. This link was demonstrated in an increased rate of motor vehicle accidents in Colorado since the legalization of marijuana there.

Mental health professionals had hoped the federal Liberal government would keep public health concerns in the forefront of its marijuana legalization. As a physician and as a parent, I am inclined to be protective where the evidence merits. But I am also realistic. I know young Canadians use twice as much marijuana as their counterparts in similar countries. I had hoped this legislation would regulate marijuana so there could be access to safe amounts only, keeping in mind the mental health of young Canadians. Having had an opportunity to consider the federal plan to legalize marijuana, health professionals will now take our concerns to provincial governments. Since the cost of negative outcomes will be borne provincially, perhaps these legislators will be more cautious with age restrictions.

More importantly, perhaps health professionals will be able to convince young Canadians and those who care for them of the health risks of marijuana use, in much the same way as we are able to convince my patients and their families. That would be the best prevention.