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Rifaximin for the Treatment of Irritable Bowel Syndrome

This study has been completed.
University of Chicago
Valeant Pharmaceuticals International, Inc.
Information provided by:
Cedars-Sinai Medical Center Identifier:
First received: November 25, 2005
Last updated: March 17, 2008
Last verified: July 2003
We have recently shown that the majority of patients with irritable bowel syndrome (IBS) have an abnormal lactulose breath test to suggest the presence of bacterial overgrowth of the small intestine. In open label and double blind treatment of IBS subjects with antibiotics, a dramatic improvement in clinical symptoms are observed. In these studies, the antibiotic chosen was neomycin, which is noted to have an efficacy of 20-25% in normalizing the lactulose breath test. A more efficacious antibiotic is needed. Therefore the aim of this study is to determine the efficacy of rifaximin in normalizing the lactulose breath test in IBS subjects with concomitant improvement in clinical symptoms.

Condition Intervention Phase
Irritable Bowel Syndrome Drug: Rifaximin Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double-Blind
Primary Purpose: Treatment
Official Title: Rifaximin in the Treatment of Small Intestinal Bacterial Overgrowth and IBS: Double Blind Randomized Controlled Trial (Multicenter Trial)

Resource links provided by NLM:

Further study details as provided by Cedars-Sinai Medical Center:

Primary Outcome Measures:
  • Global improvement in IBS

Secondary Outcome Measures:
  • Improvement in abdominal pain, diarrhea, constipation and bloating

Estimated Enrollment: 92
Study Start Date: July 2003
Study Completion Date: January 2007
Primary Completion Date: January 2007 (Final data collection date for primary outcome measure)
  Show Detailed Description


Ages Eligible for Study:   18 Years to 65 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Subjects will be selected for all studies based on the Rome I criteria. This will be the preferred method of identifying IBS patients to avoid pre-selecting patients with C- IBS. The goal is to evaluate methane as the determinant of transit, not constipation or diarrhea symptoms as through Rome II criteria. All subjects who are receiving a prokinetic drug at the time of enrollment will need to have a washout period of 7 days before starting the study protocol. Subjects will be identified through advertising in printed media and through the clinical operations of the GI motility program at Cedars-Sinai Medical Center.

Exclusion Criteria:

  • Subjects with a history of inflammatory bowel disease, diabetes, previous intestinal surgery, cirrhosis, celiac disease, probiotic use, current proton pump inhibitor use, recent antibiotic use (past 3 months), history of bowel obstruction, narcotic use or age greater than 65 years will be excluded. Most of these conditions are known to influence enteric bacteria levels. Women of childbearing years will undergo pregnancy testing before participating in the study (See below for details on the pregnancy test used). Women with positive pregnancy tests will be excluded.
  Contacts and Locations
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Please refer to this study by its identifier: NCT00259155

Sponsors and Collaborators
Cedars-Sinai Medical Center
University of Chicago
Valeant Pharmaceuticals International, Inc.
Principal Investigator: Mark Pimentel, MD Cedars-Sinai Medical Center
  More Information

Publications: Identifier: NCT00259155     History of Changes
Other Study ID Numbers: 4166
Study First Received: November 25, 2005
Last Updated: March 17, 2008

Keywords provided by Cedars-Sinai Medical Center:
Irritable bowel syndrome, Bacterial overgrowth

Additional relevant MeSH terms:
Irritable Bowel Syndrome
Pathologic Processes
Colonic Diseases, Functional
Colonic Diseases
Intestinal Diseases
Gastrointestinal Diseases
Digestive System Diseases
Anti-Infective Agents
Gastrointestinal Agents
Nucleic Acid Synthesis Inhibitors
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Anti-Bacterial Agents processed this record on June 26, 2017