SIBO Treatment Protocol

Western Medicine Perspective

In conventional medicine, SIBO is generally understood as a disorder of microbial overgrowth and disordered intestinal transit rather than simply an infection to be eliminated. The small intestine normally contains fewer bacteria than the colon, and several protective mechanisms help maintain this balance, including gastric acid, pancreatic and biliary secretions, immune defenses, intestinal anatomy, and the migrating motor complex (MMC). When these defenses are disrupted, bacterial populations may expand and ferment carbohydrates prematurely, producing gases such as hydrogen or methane and contributing to bloating, altered bowel habits, and abdominal discomfort. Methane-predominant cases are now often discussed in relation to intestinal methanogen overgrowth (IMO), reflecting the role of archaea rather than bacteria alone.

A conventional treatment protocol usually begins with confirmation or assessment of likelihood, often through breath testing and review of risk factors. Standard management may include prescription antibiotics, most notably rifaximin for hydrogen-predominant patterns, while methane-associated patterns have often been treated in research and practice with combination regimens. Clinicians may also evaluate for structural or functional contributors such as adhesions, strictures, motility disorders, celiac disease, inflammatory bowel disease, diabetes-related neuropathy, or prior surgery. In this framework, treatment is not limited to suppressing microbes; it often includes efforts to reduce recurrence by addressing constipation, impaired motility, or other predisposing factors.

Diet is commonly used as a symptom-management tool, although evidence for diet as a stand-alone eradication strategy is limited. Lower-fermentation patterns of eating, including modified low-FODMAP approaches in some patients, may reduce symptom burden by decreasing substrate available for fermentation. Elemental diets have also been studied as a more intensive nutritional strategy in selected settings, with some data suggesting they may reduce breath test abnormalities, though tolerability and practicality can be limiting. Prokinetic agents are discussed in some protocols because impaired small-bowel motility is considered a major relapse factor, but the quality of evidence varies depending on the agent and clinical context.

Overall, western medicine views a SIBO protocol as a diagnose-treat-reassess model: identify likely overgrowth, use targeted antimicrobial therapy when appropriate, investigate why it developed, support bowel function and motility, and consider retesting or reevaluation if symptoms persist. Importantly, persistent symptoms after treatment may reflect IBS, food intolerance, visceral hypersensitivity, pelvic floor dysfunction, or another gastrointestinal disorder, rather than ongoing overgrowth alone.