Does cannabis offer new hope for folks with Crohn’s disease and ulcerative colitis?

The Bottom Line

  • Around 400,000 Canadians will be living with inflammatory bowel disease (IBD) by 2030.
  • Crohn’s disease and ulcerative colitis are the most common forms of IBD. 
  • High-quality evidence to support the use of cannabis and cannabis oil in people with active Crohn’s or ulcerative colitis is lacking, so no solid conclusions around their safety and effectiveness can be made at this time.    
  • When looking into cannabis or cannabis oil as a treatment strategy, consider where the current evidence lies in your decision-making process, and speak with your health care provider about the pros and cons. 

Stomach pain, cramps, diarrhea, fatigue, rectal bleeding, fever, weight loss—these are just a few symptoms that are all too familiar to people with inflammatory bowel disease (IBD) (1-4). While people with IBD often feel embarrassed about their condition, there is no shame in it. Talking about IBD can lead to finding better ways to cope.

IBD is an umbrella term that describes chronic inflammatory conditions that affect the digestive tract—which includes the mouth, esophagus, stomach, and the small and large intestines (1-5). Crohn’s disease and ulcerative colitis are the most common forms of IBD (6). In North America, over 1.6 million people live with IBD (1;7-8), including around 270,000 Canadians—projected to be 400,000 by 2030 (9). And you guessed it…the fastest growing group of Canadians with IBD is adults aged 65 years old and over (9;10).

The cause of IBD is still a mystery, but it is thought to arise when environmental factors (e.g., infections, antibiotics, etc.) prompt the immune system to mistakenly attack microorganisms and food in the gut, producing inflammation in the digestive tract. Genetics may also play a role in increasing the risk of IBD (1-4;11). Typically, the disease alternates between periods of inactivity (a.k.a. remission) and periods when symptoms flare-up (a.k.a. relapse) (2-4).

Unfortunately, there is no cure for IBD. Instead, go-to medications often aim to reduce inflammation or suppress the immune system to get and keep people in remission (2-5). Many of these medications can come with potentially serious side effects, such as lymphoma, non-melanoma skin cancers, and liver issues (9).

One popular and highly debated alternative treatment option is cannabis (2;4). With cannabis touted as a one stop-shop for many of our medical needs, and its increasing accessibility through legalization, where does the evidence stand on its use for Crohn’s and ulcerative colitis, specifically?

What the research tells us

Two recent systematic reviewsone including patients with active Crohn’s (2) and the other including  patients with active ulcerative colitis (4)—looked at the effect of cannabis cigarettes and cannabis oil on outcomes such as disease remission or activity, inflammation, side effects, and quality of life.

When reported on, neither review found that cannabis cigarettes or cannabis oil induced remission in patients with active disease or helped with inflammation (2;4). In both Crohn’s and ulcerative colitis, cannabis cigarettes led to a reduction in disease activity (2;4), but in Crohn’s patients, this was accompanied by an increase in mild side effects such as memory loss, drowsiness, confusion, dizziness, and trouble concentrating (2). Cannabis oil produced potentially meaningful increases in quality of life in both types of IBD (2;4), but in patients with ulcerative colitis, this strategy was associated with mild to moderately severe side effects such as headache, tiredness, dizziness, nausea, and trouble concentrating (4).

So, what should patients and caregivers affected by Crohn’s and ulcerative colitis make of these findings?

Ultimately, the evidence-base around the use of cannabis and cannabis oil for Crohn’s or ulcerative colitis is not of high quality. This means, at this time, no concrete conclusions about the effectiveness or safety of cannabis and cannabis oil can be made. Ideally, future research will include a larger number of participants, account for different disease statuses (e.g., active and inactive), and evaluate different types/doses of cannabis (2;4).

If you’re considering using cannabis or cannabis oil to treat your Crohn’s or ulcerative colitis, reach out to your health care provider to help you navigate the potential harms and benefits and factor in where the current evidence lies.

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  1. Mikocka‐Walus A, Prady SL, Pollok J, et al. Adjuvant therapy with antidepressants for the management of inflammatory bowel disease. Cochrane Database Syst Rev. 2019; 4:CD012680. doi: 10.1002/14651858.CD012680.pub2.
  2. Kafil TS, Nguyen TM, MacDonald JK, et al. Cannabis for the treatment of Crohn's disease. Cochrane Database Syst Rev. 2018; 11:CD012853. doi: 10.1002/14651858.CD012853.pub2.
  3. Friedman S, Blumberg RS. Chapter 295: Inflammatory Bowel Disease. Harrison’s Principles of Internal Medicine. 18th Edition. The McGraw-Hill Companies, 2012.
  4. Kafil TS, Nguyen TM, MacDonald JK, et al. Cannabis for the treatment of ulcerative colitis. Cochrane Database Syst Rev. 2018; 11:CD012954. doi: 10.1002/14651858.CD012954.pub2.
  5. Lahat A, Lang A, Ben-Horin S. Impact of cannabis treatment on the quality of life, weight and clinical disease activity in inflammatory bowel disease patients: A pilot prospective study. Digestion. 2012; 85(1):1-8. doi: 10.1159/000332079. 
  6. Limketkai BN, Iheozor‐Ejiofor Z, Gjuladin‐Hellon T, et al. Dietary interventions for induction and maintenance of remission in inflammatory bowel disease. Cochrane Database Syst Rev. 2019; 2:CD012839. doi: 10.1002/14651858.CD012839.pub2.
  7. Crohn’s and Colitis Foundation of America. About the Epidemiology of IBD. 2012. Available from https://www.crohnscolitisfoundation.org/
  8. Rocchi A, Benchimol EI, Bernstein CN, et al. Inflammatory bowel disease: A Canadian burden of illness review. Can J Gastroenterol. 2012; 26(11):811-817. doi: 10.1155/2012/984575. 
  9. Crohn’s and Colitis Canada. 2018 Impact of Inflammatory Bowel Disease in Canada. 2018. [cited February 2020]. Available form: https://crohnsandcolitis.ca/Crohns_and_Colitis/documents/reports/2018-Impact-Report-LR.pdf
  10. Benchimol EI, Manuel DG, Guttmann A, et al. Changing age demographics of inflammatory bowel disease in Ontario, Canada: A population-based cohort study of epidemiology trends. Inflamm Bowel Dis. 2014; 20(10):1761-1769. doi: 10.1097/MIB.0000000000000103. 
  11. Abraham C, Cho JH. Inflammatory bowel disease. N Engl J Med. 2009; 361:2066‐2078. doi: 10.1056/NEJMra0804647.

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