The Science of Cannabis

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Research into cannabinoids holds great promise for advancing the potential medical uses of cannabis. Phytocannabinoids are the active ingredients in the cannabis plant. There are more than 100 of these cannabinoids, but so far research has focused on two: THC (delta-9-tetrahydrocannabinol) and CBD (cannabidiol). The human body also naturally produces its own cannabinoids called endogenous cannabinoids. The two that have been identified to date are anandamide and 2-AG.

Our body’s endocannabinoid system (ECS) has cannabinoid receptors in nervous system tissue, immune cells, bone, and joint tissue. Some medical conditions affect how the ECS works, which can lead to symptoms such as pain. Medical cannabis works by harnessing the ECS. The phytocannabinoids from cannabis supplement the endogenous cannabinoids normally produced by the body. The ECS receptors respond to the phytocannabinoids, similar to how a key opens a lock. The next steps in cannabis research will uncover more about the optimal ratio of phytocannabinoids for the best therapeutic benefits.

Canada’s Trailblazing Cannabis Research

Are you skeptical that cannabis is medicine? Beyond the anecdotal benefits, there’s a wealth of scientific evidence from clinical trials showing its safety and effectiveness. Here are the latest highlights in Canadian research that’s leading the way to making cannabis a standardized treatment option for a range of health conditions.

Safe and Effective for Chronic Pain

In December 2015 the largest study of the long-term safety of medical cannabis use by people suffering from chronic pain was published in The Journal of Pain. Called Cannabis for the Management of Pain: Assessment of Safety Study (COMPASS), it was funded by the Canadian Institutes of Health Research and conducted in seven clinical centres across the country. Researchers monitored and compared hundreds of adults with chronic non-cancer pain—about half used cannabis and half did not. For one year, the cannabis group consumed herbal cannabis containing 12.5% THC (CanniMed 12·0) daily (smoked, vaporized, or taken as edibles).

The results showed that quality-controlled cannabis has a reasonable safety profile. There was no higher rate of serious adverse events among the cannabis users, nor did they show significant change in lung, liver, kidney, or endocrine function. The cannabis users also experienced a considerable reduction in pain, and improvement in mood and quality of life.

Recommended for Neuropathic Pain

Neuropathic pain is chronic pain caused by injury, disease, chemotherapy, radiation, or surgery that affects the nervous system. The use of cannabis to relieve neuropathic pain was examined in an important clinical trial published in the Canadian Medical Association Journal in October 2010. It showed that smoked cannabis was well tolerated, reduced pain, improved mood, and helped sleep. This clinical trial was so influential that it was used in the development of the Canadian Pain Society’s 2014 treatment guidelines for neuropathic pain (Pharmacological management of chronic neuropathic pain: Revised consensus statement).  Medical cannabis is now recommended as third-line treatment for neuropathic pain.

Upcoming Clinical Trial

Researchers are currently looking for people over the age of 50 with painful osteoarthritis of the knee to participate in a clinical trial examining cannabis as a pain reliever. CAPRI (Cannabinoid Profile Investigation of Vaporized Cannabis in Patients with Osteoarthritis of the Knee) is a Health Canada-approved clinical trial on medical cannabis, and involves researchers from McGill University and Dalhousie University. In addition to validating medical cannabis as a safe and effective pain relief option, the study will compare the effectiveness of different ratios of the active ingredients THC and CBD—helping to answer whether high THC, high CBD, or a combination of the two has the greatest impact on treatment.

Consistency and Quality

Reliable research requires a trusted supply of medical cannabis at a consistent potency. Licensed producers who manufacture their cannabis following good manufacturing practices (GMP)—the same high standards used in the pharmaceutical industry—can ensure product consistency and quality control necessary to be studied in a clinical trial.

CanniMed Ltd. is one of Canada’s licensed producers of medical cannabis, and a CARP Recommended partner. To learn more about medical cannabis visit