Cannabis as a treatment for cancer-related symptoms and treatment-related side effects 

There is strong evidence to suggest that cannabis based medicines can help subside nausea and the loss of appetite caused by chemo and radiation therapy. 

Dronabinol, also known as Marinol in the capsule form or Syndros in the tincture form, is a synthetic THC drug which has been approved in the US to treat nausea and vomiting caused by these therapies. In the UK, Nabilone (Cesamet) is a licensed cannabis based drug also used to reduce extreme chemo related nausea.  

Cannabis can also be used to manage pain caused by cancer or related surgeries. Some promising studies have shown Nabiximols to be an effective alternative when strong opioid based pain medications haven’t worked. 

Cannabis could also play a role in improving quality of life for cancer patients who develop depression, anxiety and sleep disorders during the cancer treatment process. A range of THC and CBD based medicines have a proven benefit when treating these conditions.

Cannabis as a treatment to reduce or stop the spread of cancer itself 

Much more research is needed to truly understand cannabis’ potential as an anti-cancer treatment. Much of the promising evidence to date comes from animal based pre-clinical trials with a full range of detailed human studies still to be conducted. 

A 2017 study showed that cannabis’ cannabinoids possess anti cancer properties but the complexity and broad spectrum of cancers that cause abnormal cell growth mean that it’s unlikely that cannabis can be a cure in every circumstance. 

Numerous pre-clinical trials have focussed on the efficacy of cannabis as a treatment for some specific cancers:

• The use of CBD to reduce breast cancer cell invasion and proliferation was carried out with promising results in 2010.

• A 2014 study using CBD to stop the spread of colon cancer also showed reason for further investigation. 

• A 2019 review showed cannabinoids could be an effective treatment for pancreatic cancer. 

Much more is still to be discovered about the treatment of many other types of cancer with cannabis. More work is also needed to determine effective dosing, the best delivery mechanisms and possible interactions with other cancer treatments. 

Cannabis as a preventative measure to stop cancer from occurring

There is no conclusive evidence to suggest that cannabis can be used as a preventative for cancer. 

Some promising experiments conducted with mice have shown very high doses of purified THC could lower the risk of developing cancer. 

High cholesterol levels, elevated blood pressure and inflammation within the body are all issues that present a significant risk factor for cancer. CBD has been studied as a treatment for all of these issues with positive yet inconclusive results: 

• A 2011 study outlined a potential positive synergy between cholesterol metabolism-related genes and CBD use, suggesting cholesterol homeostasis in microglial cells could be regulated by CBD. 

• A 2017 study showed that resting blood pressure and blood pressure spikes in response to stress stimuli could be regulated and reduced by CBD. 

• Chronic inflammation can damage cells and cause them to divide and grow over time which in turn can lead to tumours. CBD has the ability to activate apoptosis in immune cell and suppress cytokines in inflammatory sites which in turn could inhibit tumour growth related to chronic inflammation.