Dietary and Medical Management of Small-Intestinal Bacterial Overgrowth: A Narrative Review

Small-intestinal bacterial overgrowth (SIBO) is defined by an excessive microbial presence in the small intestine and is associated with a range of gastrointestinal symptoms. Its management remains complex due to diagnostic limitations and high recurrence rates following treatment. A narrative review was conducted using MEDLINE (PubMed) and Cochrane databases to identify relevant studies published between 1984 and 2024. Search terms included small intestinal bacterial overgrowth SIBO, FODMAP, probiotics, prebiotics, synbiotics, and low-carbohydrate diets. Reference lists were also screened for additional studies. Antibiotics, particularly rifaximin, are commonly used for SIBO treatment but recurrence is frequent. Dietary strategies, such as low-FODMAP and low-carbohydrate diets, may help reduce symptoms, especially in patients with complications like D-lactic acidosis. Evidence for biotic agents (probiotics, prebiotics, synbiotics) is mixed, with limited high-quality studies and inconsistent outcomes. Some probiotic strains show symptom improvement, but effects on breath-test results are variable. A tailored, multidisciplinary approach combining dietary and medical therapies may offer optimal symptom control in SIBO. However, heterogeneity in study designs and limited evidence highlight the need for further research to inform standardised, evidence-based clinical practice.