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Mark Pimentel, MD, FRCP(C)

Executive Director, Medically Associated Science and Technology (MAST) Program

Professor of Medicine, Geffen School of Medicine

Cedars-Sinai Medical Center

Los Angeles, California

Mark Pimentel, M.D., is professor of medicine, Geffen School of Medicine and associate professor at Cedars-Sinai Medical Center in Los Angeles, California. Dr. Pimentel completed three years of an undergraduate degree in honors microbiology and biochemistry at the University of Manitoba, Canada. This was followed by his medical degree and his BSc (Med) from the University of Manitoba Health Sciences Center in Winnipeg, Manitoba, Canada, where he also completed a residency in internal medicine. His medical training includes a fellowship in gastroenterology at the UCLA Affiliated Training Program. Active in research, Dr. Pimentel has served as a principal investigator or co-investigator for numerous basic science, translational and clinical studies in such areas as IBS and the relationship between gut flora composition and human disease. His work has been published in the New England Journal of Medicine, Annals of Internal Medicine, American Journal of Physiology, American Journal of Medicine, American Journal of Gastroenterology and Digestive Diseases and Sciences, among others. Dr. Pimentel has been invited to present his work at meetings, grand rounds, and advisory boards in the United States and internationally. He is diplomate of the American Board of Internal Medicine (Gastroenterology) and a fellow of the Royal College of Physicians and Surgeons of Canada. Dr. Pimentel is also a member of several medical associations including the American Gastroenterological Association, the American College of Gastroenterology, and the American Neurogastroenterology and Motility Society.


A few of Dr. Pimentel’s most significant accomplishments include:

1. The discovery of rifaximin as a treatment for irritable bowel syndrome (IBS)

2. Developing the first blood test for IBS on the basis of IBS being derived from acute gastroenteritis

3. Describing the association between IBS and bacterial overgrowth, which forms the basis for microbiome therapies in this condition

4. Uncovering the methanogen (M. smithii) as an agent for causing constipation in humans.

5. Discovering the use of lovastatin as a microbiome treatment for constipation on the basis of inhibiting methane production by methanogens.

Speaker Disclosure Statement:

Mark Pimentel, MD, FRCP(C), has disclosed that he has received grants for clinical research from Valeant Pharmaceuticals. He has served as a consultant for and he is an honorarium recipient for Commonwealth, Naia Pharmaceuticals, Synthetic Biologics, Inc., and Valeant Pharmaceuticals. Additionally, he has participated on the advisory boards for Commonwealth, Naia Pharmaceuticals, Synthetic Biologics, Inc., and Valeant Pharmaceuticals. He is a stockholder (Not as part of a Mutual Fund) for Naia Pharmaceuticals, and Synthetic Biologics, Inc.

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