Ask the Expert: Cannabis

Controversial, stigmatized, medical breakthrough, depending on who you talk to, cannabis can be one or more of those things. We wondered what the latest research says about cannabis. Plus, with the law changing in Canada on October 17, 2018 to allow the recreational use of cannabis, we wondered what the implications of that change will be for Canadian brain tumour patients. We sat down with an expert, Dr. Lynda Balneaves, Associate Professor of the College of Nursing at the University of Manitoba, to learn more. 
Cannabis is a hot topic, not just for individuals living with brain tumours but for those affected by any type of cancer. Used to relieve seizures, nausea, and pain, it can also assist with sleep and for some of the symptoms associated with Post Traumatic Stress Disorder (PTSD), such as night terrors. There is contradictory evidence, however, if cannabis may help with the anxiety and depression experienced by some patients. Much more research is needed to understand what types of cannabis, potency and dose are most effective. 
Because of its illegal status in the United States of America (and, until recently, in Canada), it is currently very difficult to do research into cannabis. Some of the issues that researchers encounter include access to the product (sometimes taking up to two years) and in the United States, they can only access cannabis from one federal source, that is often dried, irradiated and left on the shelf for many years. Some of the research that’s been done in Canada has focussed on the role of medical cannabis for arthritis pain and spinal cord injury, as a substitute for opioids, and for addressing PTSD in veterans. In New Brunswick and Ontario, there are research centres exploring the health and social impacts of recreational cannabis. 
Outside of Canada, there have been very small human trials on individuals with recurrent glioblastoma (less than 30 people), where a significant increase in survival was observed as well as reduction in tumour size. More research is urgently needed, however, to unpack the effects and see what form of cannabis and dose are most effective. These trials have also seen cannabis being used alongside chemotherapy, raising some questions as to which treatment was ultimately making the difference.
Dr. Balneaves is passionate about ensuring that research into both medical and recreational cannabis takes place and that any available funding is distributed in a fair and equitable manner, so much so that she is recently took on a leadership role in the Canadian Consortium for the Investigation of Cannabinoids (CCIC). She hopes that the CCIC can create a collaborative network of Canadian researchers to advance the study of cannabis.  
Dr. Balneaves recognizes that as we wait for the research on cannabis to take place, many patients are moving forward with using cannabis to manage their side effects of treatment, and for some, to treat their cancer. From a safety perspective, she urges patients to talk to their doctor or nurse practitioner (NP) about their cannabis use and ensure they receive regular follow-up and monitoring of any side effects. 
This can be problematic for those who are having issues finding health care professionals who are open to the use of medical cannabis, as some are only comfortable prescribing medication that has been rigorously tested through clinical trials. Dr Balneaves recommends requesting a referral to another doctor or NP who can authorize medical cannabis use as “It is essential that patients talk to their doctors and NPs to make informed, safe decisions that will work with other medication that they may be taking.”
Even when recreational cannabis becomes legal in October, there are a few things that brain tumour patients should bear in mind. Medical cannabis is of a slightly higher standard in terms of microbes, fungus and mold compared to the cannabis that will be sold in the recreational market. It’s essential for those with a compromised immune system to get the purest cannabis possible. Recreational cannabis may also be higher in THC, for those wanting a “high”, whereas many patients will want lower THC and higher CBD or a balanced ratio, to avoid this effect. Some patients may also want to use capsules or oils to avoid potential harms caused by inhaling cannabis and to assist with long-acting symptom management. 
To learn more about whether cannabis is right for you, speak to your physician or another member of your health care team about the benefits and risks associated with medical cannabis. 
To learn more about cannabis and Health Canada’s Licensed Producers, please see FAQs on Medical Cannabis.
A special thank you to Dr. Lynda Balneaves for providing this article.
Dr. Lynda Balneaves presented "Clearing the Smoke: An Update on Medical Cannabis and Brain Tumours" at the Brain Tumour National Conference, October 20, 2018. 
Dr. Lynda Balneaves also gave a webinar on the topic: "Where There's Smoke: The Role of Cannabis in Brain Tumours" on June 20, 2017 which can be found in Online Learning.

This information is provided for information purposes only, and does not represent advice, an endorsement or a recommendation, with respect to any product, service or business, and/or the claims and properties thereof, by Brain Tumour Foundation of Canada. Always consult your health care team if you have questions about your medical care and treatments options.

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