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Cannabis legalization

My professional opinion on marijuana
By Dr. Rhonda Collins
Revera was the first company to appoint a Chief Medical Officer in the Canadian senior living sector. In her blog series, Dr. Rhonda Collins offers helpful advice for seniors to lead healthy and fulfilling lives.

Canada made history on October 17 by becoming the first major world economy to legalize the recreational use of marijuana. For cannabis activists it was a huge win after a long battle against the prohibition of the now formerly illicit drug. The change is not universally welcomed, however, as the verdict is still out on the long-term effects of cannabis use.

I, like most doctors, regularly get asked about my thoughts on cannabis from a medical perspective. First, there is a big gap in the evidence about the risks and benefits of cannabis. Multiple medical organizations including the Canadian Medical Association, the Canadian Pediatric Society and the Canadian Psychiatric Association are very concerned about the potential harmful effects of cannabis, especially in users under the age of 25. There are addiction risks. One study reports that one in seven teenagers who use cannabis develop a cannabis use disorder, meaning that their use begins to affect their daily lives in areas like school, work and relationships.
“I am eager to see some more robust evidence about cannabis in our population before feeling confident that it is safe and effective.”
For teenagers who smoke regularly, there is evidence that it can cause hallucinations and delusions, and that chronic use in adolescents causes damage to the cortex of the brain--the part that is involved in memory, attention, thinking, planning and organizing. There are also some concerns about cancer and chronic lung disease because marijuana and tobacco cigarettes contain many of the same chemicals. Since many marijuana smokers are also tobacco smokers, it is tough to determine.

There is even less information about the potential benefits and harmful effects of cannabis in our elderly and often frail population. Some of the potential adverse effects include sedation, falls, confusion and psychosis. In 2017, the Canadian Agency for Drugs and Technologies searched the literature asking the following two questions: What is the clinical effectiveness on the use of medical cannabis in the elderly? And, what are the evidence-based guidelines on the use of medical cannabis in the elderly? They found only a handful of studies and they were either too small or not well-designed enough to draw conclusions about the safety or effectiveness of cannabis in people over the age of 65. While there are currently studies underway to provide some clarity, it should be noted that these studies use medical, not recreational cannabis – yes there is a difference.

The cannabis plant produces more than 100 chemicals called cannabinoids. Two well-known cannabinoids are THC (tetrahydrocannabinol) and CBD (cannabidiol). THC stimulates brain cells to release dopamine, a chemical which helps control the pleasure and reward centres in the brain, creating a sense of euphoria or “high”. Dopamine is also implicated in addiction. The higher the concentration of THC, the greater the risk of harmful effects.

CBD does not cause a high. It is being studied for its therapeutic effects because there are cannabinoid receptors throughout the body that are activated when cannabinoids bind with them. Some of the areas being studied are pain, sleep, anxiety, movement disorders like Parkinson’s Disease and seizures. Recreational cannabis tends to have more THC because it is most often used to get high. Medical cannabis tends to have more CBD because it is used for its therapeutic effects. The percentage of THC and CBD in medical marijuana is carefully calculated to target specific symptoms while avoiding the high.

There is a real difference between medical cannabis and recreational cannabis. I am very concerned that residents, or well-intentioned families of residents, who have heard about the potential benefits of medical cannabis, will turn to recreational cannabis for symptom relief without consulting their doctors or care teams. If you are a resident of a Revera Retirement Residence or Long Term Care home it is important that you consult with the care team before consuming cannabis. Equally, if you have a loved one living in one of Revera’s Residences or Long Term Care homes, please do not bring them recreational cannabis without first consulting Revera’s care team or a physician.

In medical school we are taught primum non nocere : "First do no harm." This principal tells us that we should always consider the possible harmful effects that come from an intervention. Evidence-based practice means we use the best information from studies and guidelines, and carefully weigh the risks and benefits to provide the best care for our patients. We must always practice within the limits of our knowledge, skills and judgment, and never provide care that is beyond the scope of our clinical competence.

I am eager to see some more robust evidence about cannabis in our population before feeling confident that it is safe and effective, but I’m very happy that Revera has policies in place that simultaneously protect our residents’ rights and safety.
Dr. Rhonda Collins, Chief Medical Officer of Revera
By Dr. Rhonda Collins
Dr. Rhonda Collins brings passion and expertise in memory care, dementia, falls prevention and clinical quality improvement to the role of Revera’s Chief Medical Officer. Dr. Collins is a family physician with a certificate of added competence in Care of the Elderly from the College of Family Physicians of Canada.