Unveiling the hidden risks: analysis of adverse drug reactions associated with probiotics from the FAERS database – quality improvement study

Background: Probiotics could reduce postoperative infections and intestinal inflammation, and increase the prognostic survival rate in patients undergoing abdominal surgery. Despite its therapeutic efficacy, probiotics are also associated with some adverse drug reactions (ADRs). The FDA Adverse Event Reporting System (FAERS) database could offer several significant advantages for pharmaceutical monitoring and research. Thus, the aim of this study was to analyze the ADRs associated with probiotics using the FAERS database to guide clinical safe treatment. Methods: We analyzed the ADR reports related to probiotics from the FAERS database retrospectively. After removing duplicate entries, the final dataset comprised 8,150,023 records. ADRs related to probiotics were identified, and statistical analyses were conducted using the reporting odds ratio (ROR), proportional reporting ratio (PRR), Bayesian confidence propagation neural network (BCPNN), and empirical Bayesian geometric mean (EBGM). Results: A total of 55 ADRs induced by probiotics were found. Significant findings include high ROR and PRR values for gastrointestinal disorders, such as abdominal discomfort (ROR = 17.68, PRR = 16.87), abdominal distension (ROR = 20.88, PRR = 20.21), flatulence (ROR = 28.34, PRR = 27.68), abdominal pain upper (ROR = 7.21, PRR = 7.06), abdominal pain (ROR = 4.91, PRR = 4.84), and gastrointestinal pain (ROR = 109.48, PRR = 107.36). Uncommon disorder, including anxiety (ROR = 5.69, PRR = 5.56), agitation (ROR = 17.88, PRR = 17.55), tremor (ROR = 7.23, PRR = 7.11), suggesting very high probability of associations emerging. Conclusion: The analysis provides a detailed overview of the ADRs associated with probiotics, and both new and unexpected significant ADRs were identified, which enriched its safety profile. A process of continuous vigilance and additional investigations are imperative to verify these results, and to increase our knowledge on how probiotics should be handled in terms of its safety.