The Vulnerable Brain

"Earlier [chronological age of cannabis use] is worse, because the teenage brain is still developing and it seems like cannabis is hijacking that development. That is the problem."
"If it is going to be legalized, regulation has to be key. Just because it is [sic: will be] legal doesn't mean it is a benign drug."
Dr. Andra Smith, neuro-scientist, psychology professor, University of Ottawa

"We may be living in an environment where legalization is coming, but let's not forget about youth whose brains are developing and are at risk for mental health disorders."
Dr. Tony George, medical director, complex mental illness, Centre for Addiction and Mental Health, Toronto

"They felt that cannabis makes them better drivers, some young people reported that they felt it helped their focus and attention at school … we also heard from young people that they felt marijuana prevented and even cured cancer."
"So there's a real opportunity here to bring some clarity to this issue about what does the evidence really say about this drug and its health effects?"
"The key message is marijuana is not a benign subject. There are significant effects, whether you are looking at cognitive functioning, mental health, risk of addiction-impaired driving."
"The purpose of [Monday's public forum] was to convey that message."
Amy Porath-Waller, director of research and policy, Canadian Centre on Substance Abuse

The Canadian Centre on Substance Abuse held a town hall on marijuana's effects on youth at Ben Franklin Place in Ottawa Monday, Feb. 22, 2016. (Andrew Foote/CBC)

"I think in the end our goal [is that] the evidence is going to be compelling enough that we're going to really try to move forward on delaying use of cannabis by young people and preventing it as much as possible."
"The issues of access, minimum age, controlled sales, those are all important elements so that when people do have access to the drug they're adults, they can appreciate the effects it's going to have on their lives, they have more responsibilities, less leisure time."
Nancy Langdon, Ottawa Public Health supervisor

The Canadian Centre on Substance Abuse (CCSA) fielded its researchers and officials in a series of public forums set up for Halifax, Ottawa, Toronto, Vancouver and Calgary to interface and interact with local public health departments to ensure that their message of the potential disruptive health effects of youth smoking marijuana are well known. A kind of heads-up before the introduction by the current Liberal government of a new legalized status for marijuana, a promise made during the election campaign of last October.

That legislation is imminent, and many within society await it eagerly. Marijuana has proven to have its uses, both in a social setting for adult 'relaxation' and as a remedial health issue and pain reliever. Currently, as under the previous regime, medicalized marijuana by prescription was made legal under the auspices of the federal health department. This new looming legislation will serve to expand its legal status making it as available to adults without prescription as alcohol and tobacco.

And therein lies the concern. While legalizing marijuana is a reasonable option, removing the stigma and penalties that came with its use as a banned product where users could be arrested for breaking the law and imprisoned for its recreational use, the time has come to remove that criminal penalty under government regulatory use. At the same time because research has demonstrated that there are problems inherent in its use for developing brains of young people, which marijuana can disrupt harmfully, an alert was required.

And so, the travelling fora was born, named by the CCSA The Effects of Cannabis use during Adolescence. The Centre feels it will be necessary to protect the health of young Canadians for strict regulation to ensure that marijuana is kept out of the hands of young people. It's a little like locking the barn door after the horses have galloped off, since a drug and alcohol use survey of 2013 found that 22.4 percent of young Canadians between 15 and 19 had used cannabis, in any event.

A large crowd filled Dundas Square in Toronto as pot smokers gathered on April 20, 2011. (Peter Power/The Globe and Mail)

In fact the use of cannabis among the young appears roughly two-and-a-half times more prevalent than adults aged 25 and older using marijuana. As far as most teens were concerned, in information relayed about attitudes, conveyed during focus group interviews, there is a widely-accepted belief that marijuana is essentially harmless in its effect; simply that it is a pleasurable, mild and benign commodity which adults in their insistence on controlling and withholding pleasure from the young, characterize as harmful.

Researchers and health-care advocates are aware of a growing body of evidence that make it clear there are serious mental and cognitive issues involved for frequent marijuana users among the young. And the earlier the use of marijuana is initiated, and the more frequent its use, the more potential damage will accrue. The very architecture of the still-forming brain in adolescence can be permanently altered, quite apart from its effect in impaired executive function.

A protester lights a joint during a 4-20 marijuana rally on Parliament Hill in Ottawa  (Sean Kilpatrick/The Canadian Press)

Research has linked teens who regularly use cannabis and have used it by age 15 at least on 50 occasions, with lower test scores and a reduced academic performance in comparison with their peers who prefer not to smoke. A higher risk of psychosis and schizophrenia has also been linked to heavy marijuana use by adolescents. Swedish research revealed that people who used cannabis on more than 50 occasions by age 18 were six times likelier to develop schizophrenia than those who refrained.

Though the causal relationship between marijuana and psychosis still has room for further research, the suggestion is that those with a predisposition to schizophrenia could be vulnerable to the psychosis-inducing effects of tetrahydrocannabinol (THC), the active ingredient in marijuana. And there also looms the concern that the issue of driving under the influence of alcohol will be mirrored by rising incidents of driving under the influence of pot, presenting another scourge on the roads.

The active ingredient in marijuana is tetrahydrocannabinol or THC, which, when ingested, produces a range of effects that include a sense of well being; a feeling of relaxation; enhanced sociability; difficulty concentrating; distortions in sense of time, vision and hearing; and at higher doses, auditory and visual hallucinations. Other effects include increased heart rate, reddening of the eyes, sedation, increased appetite, and decreased muscle tone. The extent of these effects and the actual experience of the user will be determined by a number of important factors that can vary greatly.
Use of any drug has some measure of risk attached to it, and marijuana is neither a demon weed nor a benign substance. As with all substances, it is important to distinguish between casual, regular and heavy use, with negative effects being more likely with heavier use. Studies of effects are hampered because marijuana is often used in combination with other substances, particularly tobacco.