Cannabinoids for Inflammatory Bowel Disease: A Scoping Review

Purpose: Inflammatory bowel disease (IBD) has two main variants, ulcerative colitis (UC) and Crohn's disease (CD), which are characterized by a cycle of remission and relapse. The aim of this scoping review is to understand the landscape of unprescribed and prescribed cannabis use among patients with IBD and investigate objective clinical benefits. Methodology: A literature search was performed across Medline, Embase via Ovid, Scopus, and Cochrane Library databases. We included 40 studies (14 abstracts/letters, 7 randomized controlled trials [RCTs], 6 cohort studies [2 case-matched], 10 cross-sectional surveys, and 3 meta-analyses) in the review. Results: Between 11% and 17.6% of surveyed patients used cannabis for symptom control with a lifetime prevalence of 39.8-78.2%. Patients reported reduced abdominal pain, emotional distress, stool frequency, and anorexia. There was a higher rate of depression, tobacco, and alcohol use among patients with IBD who used cannabis. Individual studies showed patients who were prescribed cannabis were more likely to have had surgery for IBD (14.5% vs. 4.7%, p = 0.0008), require future abdominal surgery (odds ratio = 5.03), report a lower quality of life (p = 0.0001), currently be on corticosteroids (18.1% vs. 10.4%, p = 0.04) and opioids (27.7% vs. 6.4%, p = 0.0001). RCTs of cannabinoids reported mild reductions in disease activity and variable endoscopic inflammation improvement. Conclusions: Patients who use cannabis for IBD are a cohort with refractory disease and lower quality of life who report improvements in symptom management. However, the ability to reduce underlying disease activity appears very modest. Further trials using refined cannabinoid formulations may define a use in IBD.