Rifaximin on Visceral Hypersensitivity

Condition: Irritable bowel syndrome


Key Inclusion Criteria

  • 18-75 years old
  • Meets Rome IV criteria for IBS-D or IBS-M
  • Participants should report urgency with bowel movement at least once a week

Key Exclusion Criteria

  • Treatment with antibiotics or xifaxan in the last two months
  • History of intestinal surgery (except appendectomy or cholecystectomy)
  • Known pelvic floor dysfunction

Full Study Name

Effects of Rifaximin on Visceral Hypersensitivity in Irritable Bowel Syndrome (IRB no. 49509)   

This study focuses on individuals who have had chronic diarrhea for at least the past three months and who are at least 18 years old. The purpose of the study is to examine how well the antibiotic rifaximin (xifaxan) works in patients who have visceral hypersensitivity caused by irritable bowel syndrome with diarrhea (IBS-D) or mixed irritable bowel syndrome (IBS-M).  Visceral hypersensitivity is the term used to describe internal pain (mainly abdominal pain and rectal pain) in patients with IBS. Researchers aim to determine whether rifaximin helps decrease visceral hypersensitivity and whether decreases in visceral hypersensitivity are associated with decreases in small intestinal bacterial overgrowth (SIBO). SIBO is a common condition in patients with IBS.  

Rifaximin is approved by the U.S. Food and Drug Administration (FDA) for the treatment of IBS-D. However, it is not approved by the FDA for IBS-M and has not yet been evaluated as a treatment for visceral hypersensitivity.

Financial disclosure: Ali Rezaie, MD, who is a co-investigator on this study, receives payment from the company sponsoring the study; he serves as a consultant and has received speaker fees from the sponsor. In addition, Cedars-Sinai may receive royalties or other payments from the sponsor under the license agreement for the patent related to the drug being tested in this study.

Phase II

Principal Investigator
Nipaporn Pichetshote, MD

Medically Associated Science and Technology (MAST) Program Office