Skip to main content

Ruth A. Ross is a professor in pharmacology and toxicology, the Tanenbaum Chair in Neuroscience at the University of Toronto, and director of the Toronto Consortium for Cannabis and Cannabinoid Research. She was also president of the International Cannabinoid Research Society for 2022-2023.

When the Canadian federal government legalized cannabis on Oct. 17, 2018, its stated goal was protecting public safety. Researchers like myself were promised that in the new regime of destigmatization and decriminalization, our quest to understand the benefits and harms of cannabis would flourish as never before.

Five years later, cannabis research in Canada is still fraught with bureaucratic red tape and is chronically underfunded.

Stringent and bureaucratic regulations around research licenses and security – even though cannabis is readily available for purchase from a storefront – have substantially slowed down research efforts. As a result, there are huge gaps in our knowledge: despite self-medication by millions of people, we still do not know if cannabis is safe and effective for many conditions including pain and sleep.

This nonchalance toward the health consequences of cannabis use is irresponsible at best, and damagingly negligent at worst. But it’s not too late to turn things around.

In many respects, legalization has been a success, ensuring access to uncontaminated and unadulterated cannabis, diminishing the illegal market, and providing a lucrative revenue source for the government. But as with many pharmaceuticals and natural products, cannabis and its constituent molecules carry the very real concern of dangerous side effects. The commonly held belief that substances such as THC and CBD are natural and therefore always safe and benign is a misconception. In fact, we know that CBD can cause liver injury and alarming interactions with prescription medications.

Furthermore, for non-medical use, there has been a proliferation of very-high-potency THC products. Much of the narrative surrounding the health effects of cannabis is based on decades-old data where the concentration of THC was considerably lower than current doses, and the concentration of CBD lower still. That data is virtually obsolete in the current context. We urgently need to understand, and rapidly communicate, the risks of these products, which include cannabis use disorder, cannabis hyperemesis syndrome (chronic vomiting), driving impairment, specific risks to women (e.g. exposure to much higher levels of potent by-products of THC) and the potential for increased risk of mental health disorders including psychosis.

Governments across Canada should also fund research to provide data-driven evidence that can accompany legal sales. Some jurisdictions already do: in Quebec, all $95-million in net earnings from cannabis sales in the past fiscal year went into the province’s Cannabis Prevention and Research Fund. Operated by the Quebec Ministry of Health, this fund supports research on the effects of cannabis, as well as programs for countering its adverse effects. By contrast, Ontario Cannabis Stores (OCS), which netted approximately $170-million in the same period, has no well-defined public-health strategy on cannabis, and set aside only 0.1 per cent of its net income for a Social Impact Fund. The allocation of the fund is controlled by OCS rather than the health ministry – and it is not directed toward addressing these pressing public health questions. These examples highlight the disparate motivations of provincial governments to leverage more than a billion dollars of cannabis revenue.

That we don’t have such a system in place after five years is all the more troubling given worrying recent developments, such as the increase in cannabis use in the elderly. New products, including high potency vapes and fast-acting edibles, are entering the market with no accompanying research data. Sale of a product that has ill-defined medical parameters, unclear side effects and known risk of harms – all without a clear research strategy – is not okay.

Canada can do so much better. We have world experts in cannabis research from coast-to-coast, and we are uniquely positioned to have high-quality, well-funded research on its medical use and potential harms. In a global landscape where many jurisdictions are moving toward legalization, we can be leaders in data-driven policy.

Five years from now, will we be dealing with major public health challenges that could have been avoided? Or will we finally be able to provide patients and people who use cannabis with the knowledge that they need to make evidence-based, informed decisions about their health? These are choices only the government can make – and five years into the project of legalization, it needs to finally make them.

Follow related authors and topics

Authors and topics you follow will be added to your personal news feed in Following.

Interact with The Globe