The Effect of Probiotic and Synbiotic Consumption on the Most Prev-alent Chemotherapy-related Complications: A Systematic Review of Current Literature

Background: To date, many investigations have employed pro-/synbiotic to examine their effects on chemotherapy-related side effects; nevertheless, their findings are inconclu-sive. To address this issue, we carried out a systematic review to explore the effect of pro-/synbiotic consumption on chemotherapy-related side effects, including nausea, vomiting, mu-cositis, diarrhea, and constipation in adults using randomized controlled trials (RCTs). Methods: The electronic databases, including PubMed, Scopus, and ISI Web of Sciences, were searched systematically from the earliest available date to March 2021 to identify el-igible studies. The quality of the enrolled studies was assessed based on the Cochrane Collaboration Risk of Bias tool. Results: A total of 10 studies involving 788 individuals were included in the current systematic review, with the sample size ranging from 25 to 200 and the mean age ranging from 51.04 to 66.91 years. The findings of this study imply that probiotic consumption may be more effective in terms of mucositis compared to other complications. Conclusion: Further good-quality RCTs with better methodology are required to deter-mine whether and how pro-/synbiotics can prevent or treat chemotherapy-induced side ef-fects. The current systematic review findings may help investigators of future studies in selecting the study population and probiotic strains.