Therapeutic Effects of Cannabinoids on Ulcerative Colitis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Objective: This study aimed to perform a meta-analysis to ascertain the efficacy and safety of Cannabis in treating ulcerative colitis (UC).Material and Methods: A meta-analysis of randomized controlled trials (RCTs) included in three databases (PubMed, Google Scholar and Science Direct) was performed; from inception till 31st July 2023, so as to ascertain the efficacy and safety of Cannabis in UC. Primary outcomes included: disease activity and endoscopic indices, and quality of life (QOL). The risk of bias in the studies was assessed via the RoB2 tool.Results: In total 1,928 records identified; of which four were eligible for inclusion. The risk of bias in the included studies was moderate. The patients were randomized to the cannabinoid group had significantly improved disease activity indices (standardized mean difference (SMD) -1.78; 95% confidence interval (CI) (-2.89 to 0.67); I2=74%) and QOL (SMD -1.70; 95% CI (0.24 to 3.17); I2=75%) than those in the placebo group. However, cannabinoids did not have a significant impact on endoscopic indices (SMD -0.40; 95% CI (-0.92 to 0.11); I2=0%) nor C-reactive protein (CRP) levels (SMD -0.49; 95% CI (-0.87 to 1.85); I2=85%) of UC patients.Conclusion: Cannabinoids show potential in improving disease activity and QOL; however, their impact on endoscopic indices and CRP levels remains inconclusive.