Digestive Health Irritable Bowel Syndrome Treatment Antibiotics as a Treatment for IBS By Barbara Bolen, PhD Barbara Bolen, PhD Twitter Barbara Bolen, PhD, is a licensed clinical psychologist and health coach. She has written multiple books focused on living with irritable bowel syndrome. Learn about our editorial process Updated on July 06, 2022 Medically reviewed Verywell Health articles are reviewed by board-certified physicians and healthcare professionals. These medical reviewers confirm the content is thorough and accurate, reflecting the latest evidence-based research. Content is reviewed before publication and upon substantial updates. Learn more. by Robert Burakoff, MD, MPH Medically reviewed by Robert Burakoff, MD, MPH LinkedIn Robert Burakoff, MD, MPH, is board-certified in gastroentrology. He is the vice chair for ambulatory services for the department of medicine at Weill Cornell Medical College in New York. Learn about our Medical Expert Board Print A relatively new area of IBS research has been a focus on the use of antibiotics as a potential treatment. Not all antibiotics are thought to be helpful for IBS, just those that are not absorbed by the stomach and therefore can have an effect on bacteria within the small and large intestine. When prescribed as a treatment for IBS, antibiotics are only used on a short-term basis. Corbis via Getty Images / Getty Images Why Use Antibiotics The use of antibiotics for IBS came about when researchers looked at similarities between IBS and small intestinal bacteria overgrowth (SIBO). SIBO is a condition in which excess bacteria are found within the small intestine. Using hydrogen breath testing, researchers have found that a certain sub-set of IBS patients appeared to suffer from SIBO. Non-absorbable antibiotics were then tested for their effects on IBS symptoms. The following antibiotics have been tested as to their effectiveness in treating IBS: Rifaximin (Xifaxan) Neomycin Clarithromycin (Biaxin) Metronidazole (Flagyl) Effectiveness Of the above antibiotics, Xifaxin is the only medication that has consistently been shown to be superior to placebo in easing symptoms in a subset of IBS patients. Xifaxan appears to be most effective at relieving symptoms of bloating and diarrhea. Xifaxan is generally well-tolerated and no serious side effects have been noted. Bottom Line As of now, only Xifaxan is approved by the FDA as a treatment for non-constipation IBS. It is important to know that most of the studies to date on the use of antibiotics for IBS have been of a short-term nature. Further research needs to be conducted to assess long-term safety and effectiveness of these medications, as well as to better identify those patients who will best benefit from this type of treatment. 4 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Basseri RJ, Weitsman S, Barlow GM, Pimentel M. Antibiotics for the treatment of irritable bowel syndrome. Gastroenterol Hepatol (N Y); 7(7):455–493. Sainsbury A, Ford AC. Treatment of irritable bowel syndrome: beyond fiber and antispasmodic agents. Therap Adv Gastroenterol. 2011;4(2):115–127. doi:10.1177/1756283X10387203 Ford AC, Moayyedi P, Chey WD, et al. American College of Gastroenterology monograph on management of irritable bowel syndrome. Am J Gastroenterol. 2018;113(Suppl 2):1-18. doi:10.1038/s41395-018-0084-x U.S. Food and Drug Administration. Xifaxan (rifaximin) tablets, for oral use. By Barbara Bolen, PhD Barbara Bolen, PhD, is a licensed clinical psychologist and health coach. She has written multiple books focused on living with irritable bowel syndrome. See Our Editorial Process Meet Our Medical Expert Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Other Helpful Report an Error Submit