Small intestinal bacterial overgrowth (SIBO) is characterized by an excessive amount of bacteria in the small intestine and a constellation of symptoms that include bloating, pain, gas, and diarrhea. Although known for many decades, there is a lack of consensus and clarity regarding the natural history and methods for its diagnosis. Several tests have been proposed, including the glucose breath test, lactulose breath test, small intestinal aspiration and culture, and others. However, there is a lack of standardization of these tests and their interpretation. Treatment of SIBO remains empirical; generally, broad spectrum antibiotics are recommended for 2 weeks (amoxicillin, rifaximin, ciprofloxacin, etc.) but evidence for their use is fair. Clearly, there is a strong need to develop a systematic approach for the management of SIBO and to perform multicenter clinical trials for the treatment of SIBO. In this review, we will discuss the current evidence for the diagnosis and treatment of SIBO, which includes (1) elimination/modification of the underlying causes, (2) induction of remission (antibiotics and elemental diet), and (3) maintenance of remission (promotility drugs, dietary modifications, repeat or cyclical antibiotics).
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Conflict of Interest
Ali Rezaie reports support from the following sources for teaching, research, and consultation, outside the submitted work: Commonwealth Laboratories, Actavis, and Salix Pharmaceuticals. Mark Pimentel reports support from the following sources for teaching, research, and consultation, outside the submitted work: Commonwealth Laboratories, Salix Pharmaceuticals, Entera Health, Synthetic Biologics, Synthetic Biologics, Micropharma, and Naia Pharmaceuticals. Satish Rao reports support from the following sources for teaching, research, and consultation, outside the submitted work: Forest Laboratories, Hollister, Ironwood Pharmaceuticals, Sucampo Pharmaceuticals, In Control Medical, Vibrant, American Medical Systems, Sun Sweet Corporation, Synergy Pharmaceuticals, Salix Pharmaceuticals, and Ventrus Laboratories.
Human and Animal Rights and Informed Consent
With regard to the authors’ research cited in this paper, all procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.
This article is part of the Topical Collection on Neurogastroenterology and Motility Disorders of the Gastrointestinal Tract
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Rezaie, A., Pimentel, M. & Rao, S.S. How to Test and Treat Small Intestinal Bacterial Overgrowth: an Evidence-Based Approach. Curr Gastroenterol Rep 18, 8 (2016). https://doi.org/10.1007/s11894-015-0482-9
- Small intestinal bacterial overgrowth (SIBO)
- Glucose breath test
- Lactulose breath test
- Small intestinal aspiration and culture
- Elemental diet
- Promotility drugs