Can Pharm J (Ott). 2019 Jan-Feb; 152(1): 10–13.
Published online 2018 Dec 12. doi: 10.1177/1715163518814273
PMCID: PMC6346339
PMID: 30719190
Pharmacists should counsel users of medical cannabis, but should they be dispensing it?
Paul Grootendorst, PhD and Rajivi Ranjithan, BSc, PharmD candidate
Author information Copyright and License information Disclaimer
Canada has, since 2001, regulated the medical use of cannabis. To access medical cannabis, individuals must first obtain written authorization from a physician or nurse practitioner and then fax or mail the authorization form to a licensed producer, a commercial vendor approved and regulated by Health Canada. Licensed producers then ship the cannabis directly to the individual’s residence. Authorized individuals also have the option of cultivating cannabis for personal use. While Health Canada regulates the quality of the cannabis products available for sale (ensuring that they are not contaminated by mold or pesticide residue, for instance), there is no regulation of the levels of its 2 primary active ingredients, delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Moreover, prescribers are not required to indicate the levels of THC and CBD on the authorization form, which is known as a “medical document.” Some patients therefore have some latitude in selecting cannabis potency.
A growing number of Canadians are accessing cannabis through the regulated system. In the last quarter of 2017, there were over 250,000 authorized cannabis consumers, and the number of users is increasing exponentially. Licensed producers shipped over 40,000 kg of cannabis to consumers in 2017.1
Recently, the Canadian Pharmacists Association (CPhA) urged the federal government to allow pharmacists to dispense medical cannabis.2 The CPhA argues that pharmacists are ideally situated to help patients manage their medical cannabis use. It is unclear if the CPhA proposes that pharmacies be the exclusive distributors of medical cannabis. However, a KPMG report commissioned by the association3 did propose this.
The proposal that pharmacists oversee patients’ cannabis use has much to recommend it. Pharmacists can help avoid potentially harmful interactions between cannabis and prescription drugs. In vitro and clinical studies indicate that inhaled cannabis and tobacco induce CYP1A2, with a synergistic induction effect, which could potentially lead to drug interactions and toxicities. This is especially true for drugs with a narrow therapeutic index.4 The literature indicates that Canadians who consume cannabis therapeutically use it primarily to manage pain and insomnia, as well as alleviate psychiatric symptoms (i.e., anxiety and depression).5-7 The demonstrated effects of CYP3A4 inducers and inhibitors on THC/CBD pharmacokinetics4 suggest that people currently on sedative psychotropic agents, opioids and benzodiazepines should be advised on potential drug interactions.
Second, it appears that a majority of regular medical cannabis users use THC-rich varieties; THC is the principal euphoriant compound in cannabis. While we have no data on cannabis prescribing patterns, there is indirect evidence to support this claim. We examined the product catalogs of licensed producers in May 2018 and graphed the levels of THC and CBD of each of the dry cannabis varieties available for sale (see Figure 1). Over three-quarters of the products available had THC levels in excess of 10%.
| Figure 1
Dried cannabis sold by licensed producers, May 2018, by level of THC and CBD and cannabis strain THC, delta-9-tetrahydrocannabinol; CBD, cannabidiol. |
Regular use of high-THC cannabis can lead to psychoses,8 hyperemesis9,10 and dependence. Cannabis users have a lifetime risk of dependence estimated at 9%, rising to 25% to 50% among those who smoke cannabis daily.11 Cross-sectional studies demonstrate increased risk for development of substance use disorders in patients with substance use and a comorbid psychiatric disorder.12 Pharmacist-initiated interventions to reduce cannabis harms could be invaluable.
Finally, we have concerns over the use of cannabis in youth. The human brain continues to develop until the age of approximately 21 years.13,14 During this developmental period, the brain and endocannabinoid system14,15 are intrinsically vulnerable to the harmful effects of cannabis.13,14,16,17 Approximately 1 in 6 who initiate cannabis use in adolescence become addicted.4 Pharmacist oversight of the cannabis use of young people appears to be warranted.
While there is a sound rationale for pharmacist oversight of regular cannabis use, it is unclear if pharmacist dispensing of medical cannabis is the best route to achieve this. We see several problems.
First, the majority of regular users procure cannabis outside the regulated system18; many obtain cannabis from dispensaries, online vendors and other unauthorized channels. To give some perspective, Statistics Canada estimates that Canadians consumed approximately 773 tons of cannabis in 2017.19 The amount shipped to authorized medical cannabis users in 2017 was 40 tons or about 5% of the estimated total national consumption. Of course, some of this consumption is by infrequent users; such users likely do not require pharmacist guidance. However, a sizable share of the population consumes cannabis regularly. Our analysis of the Statistics Canada 2015 Canadian Tobacco, Alcohol and Drugs Survey (CTADS)20 found that about 5% of Canadians 15 years and older consumed cannabis either daily or weekly. Using the 2016 national population estimates, this works out to 1.8 million Canadians. The number of individuals enrolled in the medical cannabis access program is about 250,000, or only 14% of total regular cannabis users.
We could find no reliable data on the potency of the cannabis available outside of the regulated system. We therefore conducted a survey of online cannabis vendors. Figure 2 plots the levels of THC and CBD found in the product catalogs of the first 20 online vendors that appeared in a Google search of “online cannabis Canada.” Most of the cannabis varieties that we found contained high levels of THC. We also surveyed the cannabis varieties sold by 6 dispensaries (retail outlets) in the Toronto region. These varieties were also typically high in THC.
| Figure 2
Dried cannabis sold by unauthorized online vendors, May 2018, by level of THC and CBD and cannabis strain |
Thus, it appears that pharmacist cannabis dispensing will not benefit the majority of regular cannabis users, many of whom appear to be using cannabis with elevated levels of THC. It is possible that now that recreational cannabis has become legalized, the federal government will attempt to reduce unauthorized cannabis sales by stepping up law enforcement activities. If successful, this will force regular users of higher potency cannabis into the medical cannabis access program. However, from our reading of the literature, this will be difficult. The underground cannabis economy and supply chains appear to be firmly entrenched. Many users evidently prefer to obtain medical cannabis outside the regulated medical system.21 Moreover, under federal legislation, all adult Canadians will be permitted to cultivate cannabis for personal use and access recreational cannabis from government-licensed retail outlets.
The second reason that we do not favour pharmacist dispensing is that medical cannabis distributed through pharmacies would almost certainly be more expensive than cannabis sold through licensed producers or, indeed, through unauthorized channels. Most insurance plans do not reimburse medical cannabis.22 Thus, individual medical cannabis users are required to cover the cost. These additional costs would likely cause individuals to obtain their cannabis outside of the regulated medical access system.
The cost of medical cannabis sold through pharmacies would presumably include the pharmacy dispensing fee and markup. The average dispensing fee charged to private drug plans in community pharmacies outside of Ontario and Quebec is over $11,23,24 and the average markup appears to be around 8% of the drug ingredient cost. The markup and fees would presumably also be subject to the harmonized sales tax (HST).24 According to Health Canada statistics, licensed producers shipped an average of 18 grams per shipment in December 2017, the last month for which data are available.1 Assuming that medical cannabis costs $9/gram, the average shipment costs $163. An 8% markup, $11 dispensing fee and HST on these 2 items would add approximately $27 to the shipment cost. These pharmacy-specific costs likely exceed the costs that licensed producers currently incur mailing cannabis directly to registered users.
Finally, there would also be logistical problems should pharmacies receive exclusive medical cannabis distribution rights. We reviewed the online product catalogs of all licensed producers. We found that in May 2018, these vendors sold over 366 different varieties of medical cannabis that are distinguished by manufacturer, dosage form (dried cannabis flowers, oils), strains (sativa, indica, hybrids) and levels of THC and CBD, the 2 primary active ingredients. Even if cannabis users viewed the same type of cannabis produced by different manufacturers as being interchangeable, they may not view the different types as being interchangeable. We counted 267 different types of dry cannabis distinguished by strain and potency and 86 different types of cannabis oil. It would be costly for pharmacies to maintain inventories of all of these different products; it would also be costly to train pharmacists to acquire knowledge on the properties of such an extensive array of products.
We agree with the CPhA that pharmacists are ideally suited to provide patient care in this sector. But we argue that pharmacist counselling should take place in the confines of a pharmacist consultation paid for by provincial governments. These consultations would be freely available to all cannabis users, including the majority of regular users who obtain cannabis outside of the regulated system. Under our proposal, the cost of these consultations would be paid for using revenues generated by the $1 per gram excise tax that the federal government intends to levy on both recreational and medical cannabis. If these taxes are paid on just half of the 773 tons consumed by Canadians in 2017, then governments would earn about $385 million annually. Governments have already earmarked some of the excise tax revenues for cannabis harm reduction programs; pharmacist consultation programs would be in line with these initiatives. A formal pharmacist cannabis consultation program could also incorporate evidence-based counselling protocols and be subject to quality audits. These consultations would be valuable to individuals who use cannabis regularly, whether for therapeutic or nontherapeutic use.
To provide funding, policy makers would presumably require evidence that pharmacist counselling will reduce harms to regular cannabis users. There are no studies that evaluate the impact of pharmacist counselling regarding cannabis use per se. However, there is suggestive evidence from pharmacist-initiated smoking cessation interventions. Ontario has remunerated pharmacists who provide counselling on smoking cessation. A recent evaluation of this initiative estimated that 29% of smokers counselled in the first 2 years of the program had stopped smoking 1 year later.25 A systematic review conducted by the National Institute for Health Research suggests that pharmacist intervention in smoking cessation almost doubles the odds of quitting.26
Of course, these considerations do not rule out pharmacies distributing medical cannabis alongside licensed producers. This would give patients the option of procuring medical cannabis through pharmacies but would allow for less expensive alternatives as well.
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Footnotes
Contributed by
Author Contributions:Both authors collaborated on writing the article. R. Ranjithan obtained data on the prices and potency of cannabis available online and in dispensaries. P. Grootendorst compiled the other statistics reported in the paper.
Declaration of Conflicting Interests:The authors declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article.
Funding:The authors received no financial support for the research, authorship and/or publication of this article.
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