Meta-analysis finds extremely limited evidence for marijuana in Crohn's disease or ulcerative colitis
A meta-analysis of only 3 eligible trials (71 patients total) found no significant difference between marijuana and placebo for achieving remission or clinical response in IBD, with very low quality evidence.
Quick Facts
What This Study Found
For UC (1 trial, 60 patients): no difference in remission (RR 1.02) or response (RR 0.99). Adverse events higher with marijuana (RR 1.28). For Crohn's (2 trials, 40 patients): no significant difference in remission (RR 0.72) or response (RR 0.15, borderline). GRADE quality: low to very low.
Key Numbers
334 studies screened; 3 eligible (1 UC, 2 Crohn's). UC: 29 marijuana vs. 31 placebo. Crohn's: 21 marijuana vs. 19 placebo. No significant differences in remission or response. GRADE: low to very low.
How They Did This
Meta-analysis following PRISMA guidelines. Systematic search of PubMed, Embase, and Web of Science (June 2019). Of 334 studies reviewed, only 3 RCTs met eligibility. GRADE methodology assessed evidence quality.
Why This Research Matters
Despite widespread patient use of marijuana for IBD, this meta-analysis reveals that the controlled trial evidence base is almost nonexistent, with only 71 total patients across all eligible trials.
The Bigger Picture
The enormous gap between how commonly patients use cannabis for IBD and how little controlled evidence exists represents one of the most striking disconnects in cannabinoid medicine.
What This Study Doesn't Tell Us
Only 3 trials eligible; extremely small total sample (71 patients); heterogeneous cannabis preparations; GRADE quality low to very low; cannot rule out benefit that larger trials might detect.
Questions This Raises
- ?Will larger, well-designed trials reveal benefits obscured by small sample sizes?
- ?Which IBD patients, if any, are most likely to benefit from cannabinoid therapy?
Trust & Context
- Key Stat:
- Only 3 eligible trials with 71 total patients; no significant benefit; GRADE quality very low
- Evidence Grade:
- Meta-analysis with GRADE assessment, but severely limited by only 3 tiny eligible trials.
- Study Age:
- Published in 2020.
- Original Title:
- Evidence supporting the benefits of marijuana for Crohn's disease and ulcerative colitis is extremely limited: a meta-analysis of the literature.
- Published In:
- Annals of gastroenterology, 33(5), 495-499 (2020)
- Authors:
- Desmarais, Anna, Smiddy, Stephen, Reddy, Sneha, El-Dallal, Mohammed, Erlich, Jonathan, Feuerstein, Joseph D
- Database ID:
- RTHC-02510
Evidence Hierarchy
Combines results from multiple studies to find an overall pattern.
What do these levels mean? →Frequently Asked Questions
Does marijuana help Crohn's disease or ulcerative colitis?
Based on the only 3 controlled trials that exist (71 patients total), there is no statistically significant evidence of benefit. The evidence quality was rated as very low, meaning definitive conclusions cannot be drawn in either direction.
Why are there so few trials?
Cannabinoid research faces regulatory barriers, funding challenges, and difficulty blinding cannabis interventions. Despite widespread patient use, the controlled trial evidence base for IBD remains almost nonexistent.
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Cite This Study
https://rethinkthc.com/research/RTHC-02510APA
Desmarais, Anna; Smiddy, Stephen; Reddy, Sneha; El-Dallal, Mohammed; Erlich, Jonathan; Feuerstein, Joseph D. (2020). Evidence supporting the benefits of marijuana for Crohn's disease and ulcerative colitis is extremely limited: a meta-analysis of the literature.. Annals of gastroenterology, 33(5), 495-499. https://doi.org/10.20524/aog.2020.0516
MLA
Desmarais, Anna, et al. "Evidence supporting the benefits of marijuana for Crohn's disease and ulcerative colitis is extremely limited: a meta-analysis of the literature.." Annals of gastroenterology, 2020. https://doi.org/10.20524/aog.2020.0516
RethinkTHC
RethinkTHC Research Database. "Evidence supporting the benefits of marijuana for Crohn's di..." RTHC-02510. Retrieved from https://rethinkthc.com/research/desmarais-2020-evidence-supporting-the-benefits
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.