Euphoria: Researchers pinpoint cannabidiol’s safe pain relief mechanism

25 Oct 2018 --- Scientists at the Canadian Research Institute of the McGill University Health Centre (MUHC) and McGill University have pinpointed the effective dose of marijuana plant extract cannabidiol (CBD) for safe pain relief without the typical “high” or euphoria produced by the THC, further underlining the compound’s potential in offering relief to chronic pain sufferers.

Cannabis indica and sativa are the two main cannabis strains that produce the pharmacological principles known as tetrahydrocannabinol (THC) and cannabidiol (CBD). Published in the journal PAIN (The Journal of the International Association for the Study of Pain), the study shows that CBD does not act on the CB1 cannabinoid receptors like THC. Instead, it acts through the mechanism that binds specific receptors involved in anxiety (serotonin 5-HT1A) and pain (vanilloid TRPV1). 

Researchers were able to extrapolate the exact dosage of CBD displaying analgesic and anti-anxiety properties without the risk of addiction and euphoria classically produced by the THC.

Repeated treatment with CBD (5 mg/kg/day, subcutaneously, for 7 days) increased 5-HT firing through desensitization of 5-HT1A receptors, the study found.

“We found in animal models of chronic pain that low doses of CBD administered for seven days alleviate both pain and anxiety, two symptoms often associated in neuropathic or chronic pain,” says first author of the study Danilo De Gregorio, a post-doctoral fellow at McGill University.

Lead author Dr. Gabriella Gobbi sees this as advancement for the evidence-based application of cannabis in medicine with CBD offering a safe alternative to THC and opioids for chronic pain, such as back pain, sciatica, diabetic, cancer and post-trauma pain.

“Our findings elucidate the mechanism of action of CBD and show that it can be used as medicine without the dangerous side effects of the THC,” says Dr. Gobbi, who is also Professor of Psychiatry at the Faculty of Medicine at McGill University and staff psychiatrist at the MUHC. “This research is a new advancement for an evidence-based application of cannabis in medicine.

Industry and consumer interest in CBD’s potential health benefits continues to grow, further propelled also by recent regulatory changes, such as the passing of Canada's Cannabis Act on October 17, afterwhich CBD became legal in Canada. However, despite widespread public usage, little clinical evidence exists on CBD.

“More research is needed to establish the efficacy and safety on CBD in pain, anxiety and other diseases. In particular, larger clinical studies in human populations are needed to establish the real efficacy of CBD,” says Dr. Gobbi tells NutritionInsight.

Technical advancements could also come in the area of extraction, she notes.

“Several companies are working on CBD, trying to create new CBD formulations that can be patented. Many companies are also attempting to create products with 100 percent of pure cannabidiol without any THC, but the extraction is still a challenge since cannabis plants (sativa and indica) produce a percentage of THC and a percentage of CBD, with a very variable content,” she notes.

Cannabis has been tipped by nutrition and nutraceutical industry experts as an area for growth in North America, with people across different populations showing more curiosity for the ingredient as it gains increasing regulatory acceptance. Innova Market Insights data show that of the global food & beverages and supplement product launches featuring CBD in 2018 so far, the US accounts for 76 percent of launches.

By Lucy Gunn