From the Editor

Creams, gummies, drinks. Cannabidiol (CBD) is increasingly popular and found in various products. Given its supposed benefits, including as an anxiolytic, could CBD be part of a harm reduction strategy?

In new paper for The Canadian Journal of Psychiatry, Lindsay A. Lo (of the University of Toronto) and her co-authors attempt to answer that question with a rapid review of 27 studies, including 5 randomized trials, covering opioids, cocaine, and polydrug use. “Low-quality evidence suggests that CBD may reduce drug cravings and other addiction-related symptoms and that CBD may have utility as an adjunct harm reduction strategy for people who use drugs.” We discuss the paper and its implications.

In the second selection, Dr. Braden O’Neill (of the University of Toronto) and his co-authors consider cannabis clinic websites. Focusing on Ontario, they find 29 clinic websites. In new paper for Journal of Medical Internet Research, they look at the claims made, and analyze the supporting literature. “The recommendation of cannabis as a general therapeutic for many indications unsupported by high-quality evidence is potentially misleading for medical practitioners and patients.”

And in the third selection, Dr. Jeremy Devine (of McMaster University) writes about federal drug policy in an essay for The Toronto Star. He feels that the current approach to the opioid crisis is flawed, with its focus on “regulation” – and he is particularly critical of safe supply programs. “The core ideological flaw in our drug policy is that it fails to recognize a hard truth: the drug user cannot have both their addiction and a free, safe, and self-determined life.”


Selection 1: “Cannabidiol as a Harm Reduction Strategy for People Who Use Drugs: A Rapid Review”

Lindsay A. Lo, Caroline A. MacCallum, Kate Nanson, et al.

The Canadian Journal of Psychiatry, 27 June 2023  Online First

Recent cohort studies revealed that individuals at high risk of overdose commonly substitute cannabis for more harmful drugs (e.g., stimulants and opioids) as a harm reduction strategy. Further, individuals reporting difficulty accessing addiction treatment or who used substances with limited treatment options, such as methamphetamines, had a higher likelihood of using cannabis as a harm reduction strategy…

The vast majority of evidence for cannabis as a harm reduction strategy is focused on THC-dominant products or does not distinguish between cannabinoids. However, preclinical and emerging clinical evidence has shown that CBD may act as an anxiolytic, antidepressant, and antipsychotic, as well as having procognitive and neuroprotective effects… CBD is non-intoxicating and has a significantly reduced side effect profile compared to THC. The lower risk of abuse and severe adverse psychiatric events, such as psychosis, is particularly desirable as the negative impact of high-dose THC is a common concern regarding the use of cannabis within this population.”

So begins a paper by Lo et al.

Here’s what they did:

“A systematic search in EMBASE, MEDLINE, CENTRAL, and CINAHL was completed in July 2022. For inclusion, studies had to meet the following criteria: (1) drawn from an adult population of people who use drugs; (2) investigates CBD as an intervention for problematic substance use or harm reduction–related outcomes; (3) be published after the year 2000 and in English; and (4) be primary research or a review article. A narrative synthesis was used to group outcomes relevant to harm reduction and provide clinical and research insights.”

Here’s what they found:

  • Opioids. “One RCT reported that acute CBD administration of 400 and 800 mg oral CBD significantly reduced cue-induced craving and anxiety compared to placebo. Differences were most pronounced within 24 h post-CBD ingestion. However, differences in placebo were also detected 7 days post-dose. Two pilot studies similarly reported success in the reduction of drug-cue-induced craving.”
  • Cocaine. “One RCT reported across 3 manuscripts examined 800 mg/day of CBD in individuals with cocaine use disorder and found no evidence that CBD was more efficacious compared to placebo in improving cognitive outcomes, modulating anxiety symptoms or cortisol levels, reducing cravings and withdrawal symptoms, or preventing the resumption of cocaine use. Similarly, another RCT investigating 300 mg/day of oral CBD cocaine-dependent individuals found no difference in craving levels, anxiety, depression, or sleep compared to the placebo.”
  • Polydrug use. “The qualitative study examining experiences of PWUD accessing a cannabis distribution program reported high popularity of CBD use in their sample. Participants reported improved pain, reduced cravings, better sleep, more energy, and general feelings of wellness. The cross-sectional study reported a low prevalence of frequent CBD use overall (9%), with self-reported benefits in frequent CBD consumers, including improved relaxation, anxiety, sleep, and pain.”
  • Gaps in evidence. “All studies noted the need for more human research, particularly larger-scale clinical trials.”
  • Quality of evidence. “The quality of included studies was assessed to be low. All RCTs were assessed as having a high risk of bias…”

A few thoughts:

1. This is an interesting study that is practical and balanced.

2. The findings: “there is some indication that CBD may help reduce opioid drug craving and anxiety. There is limited support for cocaine drug craving and relapse as of now. There was some indication that CBD may be beneficial in improving mood and general well-being…”

3. As the authors outline, the quality of the studies wasn’t particularly robust. They summarize the risk of bias in the RCTs:


4. The authors make additional points about the limitations of a (pure and rigid) CBD strategy. For instance, would a more mature approach be to use CBD during the day and THC at night or perhaps offer varied doses at different times?

5. Some of my patients have described CBD as essential to their recovery. At this point, the enthusiasm for CBD in harm reduction is greater than the evidence found in the literature.

The full CJP paper can be found here:

Selection 2: “Evaluating the Supporting Evidence of Medical Cannabis Claims Made on Clinic Websites: Cross-Sectional Study”

Braden O’Neill, Jacob Ferguson, Lauren Dalueg, et al.

Journal of Medical Internet Research, 29 June 2023

A multibillion dollar cannabis industry has emerged in Canada after its medical use was legalized in 2013 and recreational use was legalized in 2018. Before 2018, authorized medical cannabis was procured from federally licensed producers under the Access to Cannabis for Medical Purposes Regulations. After recreational legalization, federally licensed producers in Ontario revoked their medical designations, as any consumer, medical or recreational, could obtain their cannabis from any licensed dispensary, in addition to growing or producing it themselves. After 2018, ‘medical cannabis’ could be any cannabis product, including the same products used recreationally but obtained with a medical indication. Overall, these changes have also fostered societal shifts in cannabis use among some segments of the population; for instance, among adolescent males, substance-related hospitalizations after cannabis legalization have increased 30% in Quebec. Modest increases in cannabis use among middle- and older-aged adults have also been seen after legalization…

There is a paucity of high-quality evidence demonstrating the effectiveness of cannabis for medical purposes. A recent systematic review on the use of medical cannabis found some low- to moderate-quality evidence to support its use for nausea and vomiting after chemotherapy, for spasticity from multiple sclerosis, and for neuropathic pain, but no high-quality evidence supporting its use for other indications, such as osteoarthritis pain. Despite this uncertainty in the evidence base, there has been an explosive proliferation of cannabis clinics and physicians prescribing cannabis throughout Ontario…

So begins a paper by O’Neill et al.

Here’s what they did:

“We conducted a cross-sectional web search to identify all cannabis clinic websites within Ontario, Canada, that had physician involvement and identified their primary purpose as cannabis prescription. Two reviewers independently searched these websites to identify all medical indications for which cannabis was promoted and reviewed and critically appraised all studies cited using the Oxford Centre for Evidence-Based Medicine Levels of Evidence rubric.”

Here’s what they found:

  • Of 76 potentially eligible cannabis websites, 47 were excluded for various reasons. 15%, for instance, had a website link that no longer worked.
  • Medical indications. A total of 29 clinics were identified, promoting cannabis for 20 medical indications including post-traumatic stress disorder (69% of websites), HIV (35%), and cancer (48%).
  • Studies cited. Studies tended to have enrolled adults (92.8%) and included 1,311,211 participants in total…” The median per study was 128 participants.
  • Quality of evidence. There were 235 unique studies cited “to support the effectiveness of cannabis for these indications… A high proportion (15.3%) of the studies were identified to be at the lowest level of evidence (level 5).” Just 3% were of the highest.
  • Harms. “Only 4 clinic websites included any mention of harms associated with cannabis.”

A few thoughts:

1. This is a good study, and it’s very timely.

2. The major finding in a sentence: “Cannabis clinic websites generally promote cannabis use as medically effective but cite low-quality evidence to support these claims and rarely discuss harms.”

3. Just four clinics mentioned any potential harms with cannabis use. “It was striking that few clinics described the harms of medical cannabis, especially when there is evidence suggesting that cannabis may be more likely to cause harm to patients rather than benefit them. Specifically, many cannabis-prescribing clinics in Ontario claim to treat conditions for which cannabis may not be safe.” Ouch.

4. Of course, such advertising presents challenging for patient care. “The web is a widely used health information resource; a nationally representative survey found that two-thirds of Canadians looked for health information on the web in the past year…” Let the buyer beware? Should websites be better regulated?

The full JMIR paper can be found here:

Selection 3: “The federal drug strategy is not helping the addicts”

Jeremy Devine

The Toronto Star, 17 July 2023

Canada’s response to the opioid epidemic is failing. Despite a federal commitment of more than $1 billion since 2017, opioid overdose deaths have steadily risen; since 2016, more than 36,000 Canadians have lost their lives to an opioid overdose.

Although our leaders believe they have brought Canada to the vanguard of a progressive drug policy, homelessness, public disorder, and deaths continue to mount.

As a practicing psychiatrist, I routinely encounter patients struggling with addiction who are suicidal, disaffected, and seemingly resigned to a life on the margins. Working in emergency departments, community clinics, and locked in-patient wards, I am reminded daily of our wholly inadequate addiction treatment system, especially for those without financial means.

So begins an essay by Dr. Devine.

He expresses concern that “our approach is further oppressing the drug user.” He argues: “Because they have uncritically embraced the dogma of anti drug-prohibition activists, public health authorities are under the erroneous impression that they can successfully ‘regulate’ the drug user in a state of active addiction.”

“Since 2017, the Federal government has approved 38 supervised injection sites, decriminalized hard drug use in British Columbia, and generously funded so called ‘safe supply’ programs which feature the delivery of potent opioids directly to the drug user with minimal oversight.”

He notes that the Stanford-Lancet Commission on the North American Opioid Crisis “explicitly condemns safe supply programs.” “In addition to raising obvious safety issues, the report rightly warns that supplying opioids to the addicted risks glazing over deeper issues of poverty, trauma, and social exclusion which frequently lie at the root of addiction. One of the authors, acclaimed addiction specialist, Dr. Anna Lembke, has called safe supply the ‘chemical abandonment’ of the drug user, while the report itself cautions against ‘the pharmacological sedation of poverty.’”

He disagrees with federal drug policy which has taken “policy cues primarily from anti drug prohibition and safe supply activists who view chronic and compulsive drug use as ‘an integral part of somebody’s life.’ Most drug users, let alone their loved ones, do not view their drug use as ‘integral’ to their life, but rather as a terrible affliction from which they desperately want their freedom.”

A few thoughts:

1. This is a well-argued essay.

2. He doesn’t mince his words: “To be addicted is to be a slave.”

3. Dr. Devine raises good points, including around safe supply and evidence. Others agree to disagree. The Globe and Mail recently published an editorial on this topic, “Unrelenting drug overdose deaths demand an unrelenting policy response from governments.” The editorialists argue that: “Treatment should be everyone’s end goal. As this space has too often noted, the dead cannot be checked into rehab. But to focus on treatment while minimizing or ignoring a range of harm reduction is a mistake – as is the reverse, too much work on harm reduction without ample treatment beds. Treatment absolutely must be available to those who seek it but relapse after initial treatment for opioids addiction is common. To not invest in services like supervised drug-use sites is a grave error. That health policy serves 2,600 Canadians a day, has made almost 300,000 referrals to other services such as mental health and housing, and has never had a person die on site.”

They continue: “Safer supply gets a lot more public attention – and attacks from the likes of federal Opposition Leader Pierre Poilievre – than its actual impact to date. In early June, B.C. officials said less than 5 per cent of people using drugs have been prescribed access.”

That editorial can be found here:

4. Do you have opinions on Dr. Devine’s essay? The Reading of the Week invites letters to the editor.

The full Toronto Star essay can be found here:

Reading of the Week. Every week I pick articles and papers from the world of Psychiatry.