Medical Marijuana and the treatment of Colon Cancer

Colon cancer affects the large intestine. Colon and rectal cancers are the second leading cause of cancer deaths in the US, expected to to cause over 50,000 deaths in 2017 and many more around the world.

More and more good research suggests that cannabis and cannabinoids might play an important role in the possible treatment and management of a wide variety of cancers. So could medical marijuana also help cure colon cancer?


Colon cancers are often grouped together with rectal cancers and collectively referred to as colorectal cancer. Colon cancer is characterized by the formation of malignant tumors in the large intestine (or colon).

The large intestine serves as the last part of the digestive tract. It plays the vital role of absorbing water and nutrients from digested food before turning it into feces.

Both colon and rectal cancers typically start as small, benign growths known as polyps. These polyps usually form in the inner lining of the intestine and can become cancerous after time.

There are 2 main types of polyps that can form in the colon or rectum; adenomatous (adenomas) and hyperplastic polyps.

Hyperplastic and inflammatory polyps are more common but generally don’t become cancerous. Adenomas, on the other hand, are more likely to become cancerous.

There are a number of factors that can influence whether or not a polyp develops into cancer. Patients with large or multiple polyps (more than 2) are generally considered to be at a higher risk of having the polyps become cancerous.

Dysplasia, a condition in which the tumor cells look abnormal yet don’t resemble true cancer cells, is also associated with an increased risk of having polyps develop into cancer.

Colon cancers will eventually grow into the wall of the large intestine. In doing so, they may reach blood or lymph vessels, at which point they can spread to nearby lymph nodes or other parts of the body. However, it is important to remember that not all polyps become cancerous.


Some symptoms commonly associated with colon cancer include:

  • A change in bowel habits (such as diarrhea, constipation or a change in consistency) lasting more than 4 weeks.
  • Rectal bleeding or bloody stool.
  • Persistent abdominal discomfort, such as pain and cramps.
  • Weakness or fatigue.
  • Unexplained weight loss.

Most patients will not experience symptoms in the early stages of the disease. Symptoms will also vary from one patient to another, depending on the size and location of their individual cancer.


For a while now, there is a growing body of research exploring the relationship between cannabinoids and cancer. But while there is still no solid consensus among the medical community about how cannabis and its compounds can affect the growth of tumours, recent research has produced some interesting results.

A number of studies have looked at the exact effects of cannabinoids on colon cancer. One study, published in the Journal Of Molecular Medicine in 2012, studied the effects of cannabidiol (CBD) on colon cancer in mice.

The study found that CBD had clear anti-cancer effects. It counteracted the effects of azoxymethane (a carcinogenic and neurotoxic chemical used to induce cancer in biological research), reducing the formation of polyps and tumours.

Meanwhile, the study also observed that CBD helped protect DNA from oxidative damage, increased endocannabinoid levels and reduced cell proliferation. A follow up study suggested that CBD produced these effects by interacting with CB1 receptors, suggesting that the endocannabinoid system is closely involved in the management of cancers and tumours.

Another trial, published in the Journal of Clinical Investigation in 2004, also used a mouse model to explore the effects of cannabinoid signalling on colon cancer.

The study found that the activation of the endocannabinoid system (ECS) by both phyto and endocannabinoids helped protect against colonic inflammation. This suggests that the ECS and cannabinoids may play an important role in the management and treatment of colon cancer.

Besides these studies, a much larger body of research has explored the effects of the ECS and cannabinoids on cancer in general.

For example, a 2014 study published in Life Sciences showed that tetrahydrocannabinol (or THC, the main psychoactive ingredient in cannabis) effectively reduced the size of melanoma tumors in mice.

A 2011 article from the Cancer Prevention Research Journal, on the other hand, also showed that cannabinoids and other CB1 and CB2 agonists were able to slow the growth and spread of lung tumors.


Countless other studies have explored the effects of cannabinoids, both plant-based and endogenous, on the development and spread of a wide variety of cancers, including brain tumors, leukemia, liver and more.

Besides this research, there’s also a large body of anecdotal evidence from patients who claim they were able to beat cancer using cannabis medicine.

However, anecdotal evidence isn’t always highly regarded in the field of medical research. Nonetheless, together with the growing body of evidence from clinical and other controlled trials, stories from patients make it clear that cannabis and the ECS might play an important role in the management of all kinds of tumours, including colorectal cancer.

Hopefully, with further investigation into the relationship between cannabis and cancer, we’ll soon be able to make concrete conclusions about how cannabinoids may help treat and contain tumours like those of colon cancer.

Note: We have taken the utmost care and precaution whilst writing this article. That being said, please take note of the fact that we are not medical professionals of any kind. is strictly a news and information website. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment.