• Marijuana is the drug extracted from the common hemp plant cannabis.
  • It contains both mind-altering compounds such as tetrahydrocannabinol (THC) as well as compounds that do not have mind-altering effects such as cannabidiol (CBD).
  • The human body has a endocannabinoid system (ECS) that works via endocannabinoids and receptors. It controls a variety of things, such as inflammation, nausea, sleep and appetite.
  • In animal and test tube studies, cannabis as been shown to combat inflammation.
  • In studies on people with IBD, cannabis has not been shown to objectively reduce inflammation. However, it has been proven to increase quality of life and reduce symptoms.
  • Further research is needed as compounds in cannabis show great potential for development of drugs to treat IBD. Science still needs to figure out the best way to use this compounds to find a possible cure.
  • Until then, even if cannabis has not been proven to treat the underlying mechanisms triggering IBD, it has definitely been shown to be effective for symptom control.
  • Therefore, it may be worth a try. As anyone with IBD would agree, a reduction in symptoms would make a world of difference. It is the symptoms that make living with IBD such a challenge.

New Possibilities for Treatment

As many of us have realized, standard medical treatment options for ulcerative colitis, pancolitis, and Crohn’s disease have varying levels of effectiveness among different patients, with many struggling with abdominal symptoms even while on treatment. Marijuana1 has been used for therapeutic purposes for thousands of years, and anecdotal evidence suggests that cannabis has been used by people with inflammatory bowel diseases (IBDs) for hundreds of years. Due to legality issues surrounding cannabis, investigation into the effectiveness of marijuana in treating these illnesses has advanced slowly. With the legalization of medical marijuana rapidly progressing, the medical community has finally been able to start subjecting the therapeutic claims of cannabis to rigorous scientific scrutiny.

Cannabis plant

Cannabis Terminology

If you’re acquainted with the basic terms related to marijuana, skip to the next section.

For our purposes, we’ll use this to refer to the flowers and leaves of the cannabis plant, as opposed to the uses of hemp fiber for clothing and a thousand other things. The flowers are typically dried and smoked, or eaten or taken as a pill or a distillate, like oil. Cannabis contains psychoactive compounds and others which are not mind-altering, which we’ll detail below. How cannabis affects you depends on what type of cannabis you consume and on your body.
Tetrahydrocannabinol (THC)
A psychoactive compound released by the cannabis plant. It produces mind-altering effects, heightening the senses and altering your perception of time. THC also has therapeutic effects: pain relief, reduced nausea, and improved sleep, depending on the individual, the strain, the quantity and the method of ingestion.
Cannabidiol (CBD)
This is another well-known compound found in the cannabis plant, only discovered in 1940 and overshadowed until recently by its psychoactive cousin, THC. But unlike THC, cannabidiols have no mind-altering effects while offering numerous therapeutic benefits like pain relief, reduction of inflammation, and protection of the nervous system. Some CBD products contain THC and can be mind-altering. Others don’t and have no mind-altering effects. While the legality of THC, CBD, and combinations of the two depend on local regulations, products exclusively containing only CBD are more likely to be legal to buy and use.
Endocannabinoid system (ECS)
The recently identified biological system regulates homeostasis, or broadly, stability of the physiological mechanisms that take place in our bodies. Cannabinoid receptors are found all over the body, acting as a bridge between mind and body.

How Cannabis Works on Inflammation in the Gastrointestinal Tract

The mechanism by which some scientists believe cannabis can be used to treat inflammation in the gastrointestinal tract is via the interaction of cannabis and the endocannabinoid system (ECS). The ECS regulates such processes as inflammation in the intestines, gastrointestinal (GI) motility, the transport of ions, controlling the intake of nutrients, the growth of cells in the gut, and gastric secretion. Cannabinoids interact with the ECS, which in turn controls various processes in the body. The three types of cannabinoids are:

which are cannabinoids found in plants.
Synthetic cannabinoids
which are man-made.
which are created by the body.

Endocannabinoids are naturally present in the body and are continually interacting with the ECS. Synthetic cannabinoids have been used by the medical community since the early 1980’s, but synthetic cannabinoids haven’t been able to replicate the therapeutic benefits of cannabis. Scientists are interested in studying how phytocannabinoids can treat IBD because endocannabinoids can only be created by the body and synthetic cannabinoids are not yet able to mimic the therapeutic effects of phyto- or endocannabinoids.

Cannabinoids act upon receptors in the ECS, many of which are in the gut. When cannabinoid receptors are activated, they can produce beneficial effects such as reducing inflammation in the intestines. Cannabinoids also increase appetite, reduce nausea, and improve sleep. This is why IBD patients and scientists are so interested in cannabis as a potential treatment option for ulcerative colitis and Crohn’s disease.

What the Science Says

Scientists are optimistic cannabis can be used to treat chronic inflammation of the gastrointestinal tract for the following reasons:

  • Because doctors suspect endocannabinoid deficiency could be one of the mechanisms contributing to these diseases.
  • Because cannabis has been recognized for centuries as an anti-inflammatory.
  • Because cannabis has fewer known side-effects compared to conventional treatments/medications.


A 2005 pilot study surveyed patients with ulcerative colitis and Crohn’s disease to see how they felt after using cannabis2. The patients reported benefits such as improved appetite, fewer bowel movements, decreased nausea, reduced vomiting, and improved energy levels, as well as fewer symptoms of depression and a general reduction in the number of flare-ups.

Other researchers began gathering data from ulcerative colitis and Crohn’s disease patients in 2011 and concluded cannabis appeared to provide symptom relief. In 2013, a placebo-controlled study didn’t go as far as to conclude marijuana cures these illnesses, but researchers did determine that cannabis reduced symptoms, demonstrating a 90% decrease on the Crohn’s disease activity index.3


With the discovery of CBDs, researchers realized that the impact of phytocannabinoids could be studied without patients being subjected to the psychotropic effects of THC. A 2013 review showed that while CBD has not been proven to be a conclusive cure for ulcerative colitis and Crohn’s disease, it does show promising potential for the development of a new class of treatment option for IBD.4 Other studies done in test tubes have confirmed CBD reduces intestinal inflammation5 and protects the colon from injury when colitis is induced in mice.6

CBD or THC: Which is Better?

Which is better, CBD or THC? A study conducted in 2010 examined this question by giving THC and CBD to rats with colitis7 and found THC to be the most effective. However, researchers also found that when CBD was added to very low (ineffective) doses of THC, it rendered the THC effective.

Research Findings

A 2017 study on the effects of low dose CBD on ulcerative colitis and Crohn’s disease indicated that scientists can’t yet demonstrate consistent symptom improvement from CBD, though they did conclude that it was safe.8 The authors suspect that the lack of demonstrable results could be explained by the low dosage used in the trial, lack of other cannabinoids (the so-called entourage effect, the idea that non-psychoactive compounds in cannabis modulate the effects of the psychoactive compound, THC9), or the small sample size.

Over the years, not many conclusions on cannabis as a treatment for inflammatory bowel diseases have been reached. Also, previous studies have not indicated the means by which cannabis relieves intestinal inflammation. In mid-2018, the scientific community finally received some hopeful news. For the first time, the biological mechanism by which cannabis could alleviate intestinal inflammation in the gastrointestinal tract was identified. The body’s endocannabinoid system protects the intestines from becoming inflamed by helping produce molecules which stop the immune system from destroying the layer of cells which protect the inside of the intestines. This shows potential for phytocannabinoids from cannabis to help fight inflammation the same way endocannabinoids do, which could be useful when the body does lacks sufficient endocannabinoids.10

Another key study released in October 2018 was a randomised, placebo-controlled study done by researchers from Tel Aviv University, investigating the effects of cannabis oil on gut inflammation.11 They gave 46 participants either cannabis oil or a placebo. Then, they measured symptom severity and quality of life in these patients. They also checked actual inflammation levels through blood tests and stool samples to check for inflammatory markers as well as endoscopic procedures to directly assess the gut. Most patients reported significant improvements in symptom control and quality of life, which is great news! However, the researchers found no real changes in endoscopy and blood test results.

Looking into Treatment

If you are considering treating your ulcerative colitis, pancolitis or Crohn’s with medical marijuana, there are some factors to consider:

  • Whether you have the legal means to obtain cannabis.
  • If you are able to coordinate a medical marijuana treatment plan with your doctor.
  • Whether to treat with THC, CBD or both.
  • What dosage to take.
  • Which form of cannabis to use.

Researchers have been looking into how best to administer CBD and THC to patients suffering from inflammation of the gastrointestinal tract. To effectively deliver CBD to the small intestine where it can reduce inflammation, one method is to use enteric12 coated capsules. These capsules are specially designed not to release their contents in the acidic stomach environment, but rather in the alkaline small intestine.

An example of how to use cannabis to treat ulcerative colitis was reported by a Dutch teenager who was searching for a solution which didn’t involve getting high or smoking. The boy and his father experimented with vaporizers and edible options before seeing promise with a daily THC dose of 12mg, ingested orally. Within one week the boy experienced a marked reduction in symptoms. The boy and his father continued to fine-tune the regime before settling on a daily dosage of 50mg of CBD by pill and 12mg of THC in oil form taken sublingually.13 The sublingual method of consuming medical cannabis is preferable because it is more discreet, takes effect faster without losing effectiveness or duration, and avoids the health hazards of smoking.

Many cannabis studies which use animal models inject cannabis into the lining of the animal’s abdominal cavity, which is not a viable option for human patients. At least one study has suggested cannabis should be administered via suppository to ulcerative colitis and Crohn’s patients, but the evidence seems to suggest THC cannot be absorbed rectally.14 Some patients do find relief administering cannabis via suppository, but more research is needed.

How to Access Cannabis-Based Treatment

As of writing, thirty countries have some kind of access to medical marijuana, and many more are continuing to legalize.

If you have access to medical marijuana and are interested in treating your ulcerative colitis and Crohn’s symptoms, you should consult their doctor to figure out the best treatment methods for you.

If you do not have access to medical marijuana but still wish to purchase and use unregulated cannabis products, take the time to do extra research and proceed with great caution in view of both legal consequences and health risks. Be sure to find accurate information about dosing, potency, strain, and make sure your cannabis doesn’t contain unwanted material such as pesticides, residues or mold.


If conventional medical treatment is not helping your inflammatory bowel disease, or if it is helping to a certain extent but you still have symptoms, you may want to consider using cannabis to treat your ulcerative colitis, pancolitis, or Crohn’s disease.

Science has not yet demonstrated that cannabis is a cure, but it has shown that medical marijuana has great potential to be an effective treatment option, with more research needed on the best methods, types, and dosing.

Research has clearly demonstrated that cannabis helps relieve symptoms and improves quality of life in a vast majority of patients with IBD. This, coupled with its low risk (besides legality concerns in jurisdictions where it’s prohibited) and cost suggest that medical marijuana may be well worth trying if you haven’t responded sufficiently to other treatments, or need further symptom control.

  1. This is the colloquial name for the drug extracted from cannabis – that is, the common hemp plant.
  2. Cannabis Alleviates Symptoms Of Crohn’s Disease (2005)
  3. Cannabis finds its way into treatment of Crohn’s disease (2013)
  4. Cannabidiol in inflammatory bowel diseases: a brief overview. (2012)
  5. Cannabidiol reduces intestinal inflammation through the control of neuroimmune axis (2011)
  6. Cannabidiol, a safe and non-psychotropic ingredient of the marijuana plant Cannabis sativa, is protective in a murine model of colitis (2009)
  7. The effects of Delta-tetrahydrocannabinol and cannabidiol alone and in combination on damage, inflammation and in vitro motility disturbances in rat colitis (2010)
  8. Low-Dose Cannabidiol Is Safe but Not Effective in the Treatment for Crohn’s Disease, a Randomized Controlled Trial (2017)
  9. An entourage effect: inactive endogenous fatty acid glycerol esters enhance 2-arachidonoyl-glycerol cannabinoid activity (1998)
  10. Intestinal P-glycoprotein exports endocannabinoids to prevent inflammation and maintain homeostasis
  11. https://www.ueg.eu/press/releases/ueg-press-release/article/ueg-week-cannabis-significantly-improves-the-symptoms-of-crohns-disease-despite-having-no-effect-o/
  12. A polymer barrier that doesn’t disintegrate in the stomach
  13. Under the tongue
  14. Topical and systemic cannabidiol improves trinitrobenzene sulfonic acid colitis in mice (2012)

Yury Tsukerman