Exploring Mechanisms and Therapeutic Strategies for Metformin Hydrochloride-Induced Diarrhea and Gastrointestinal Intolerance: A Bibliometric Analysis

Background: Metformin hydrochloride (MET) gastrointestinal adverse effects (GAEs) are associated with intestinal accumulation, gut microbiota alterations, transporter saturation, and increased serotonin and lactate levels. This study mapped the scientific literature indexed in Web of Science (WoS) and Scopus, with MET-induced gastrointestinal intolerance and diarrhea as the primary research focus, concentrating on mechanisms and strategies to mitigate GAEs. Methods: This bibliometric analysis followed the PRISMA and PICO guidelines. WoS and Scopus were searched using terms derived from DeCS/MeSH descriptors. Two independent reviewers performed study selection. Data were analyzed using Bibliometrix (biblioshiny) in RStudio for performance analysis, scientific mapping, and collaboration networks. Results: A total of 6998 articles were identified, resulting in the inclusion of 153 studies (116 original articles and 37 reviews), distributed across 117 journals. The annual growth rate was 4.74%, with a peak in productivity between 2022 and 2025, and an average of 45.01 citations per document. GAEs constituted the most investigated area (28.1%), followed by molecular mechanisms (11.8%) and associated comorbidities (10.5%). The United States led scientific production (n = 37), followed by China (n = 18) and India (n = 17). Conclusions: Despite advances in understanding mechanisms, interventional studies and therapeutic strategies remain underrepresented. Strengthening international collaboration and participation from low- and middle-income countries is essential to develop more effective and equitable approaches.