Clinical Study

Treating Bacterial Overgrowth In Parkinson's Disease

Posted Date: May 17, 2017

  • Investigator: Alberto Espay
  • Specialties:
  • Type of Study: Drug

Many people with Parkinson’s disease (PD) also have too much bacteria in their small intestine, a condition called Small Intestinal Bacterial Overgrowth (SIBO). SIBO can be treated using an antibiotic medication called Rifaximin. The purpose of this research study is to investigate whether people who have PD and SIBO may benefit from treatment with Rifaximin to help control their symptoms. Although SIBO is common in people with PD (about half), you could have this condition without knowing it. It is also possible that the bacteria in your intestine could affect the way your Parkinson’s medications work. This study will help us understand the relationship between intestinal bacteria and how well your symptoms are controlled by your medications. This study will involve one or two rounds of treatment with Rifaximin and/or a placebo (a look-alike pill with no active ingredient). It is a blinded, placebo-controlled study. That means that you won’t know when you are taking Rifaximin or the placebo. However, you are guaranteed to take the real drug at least once during the study. You can find out whether or not you are receiving Rifaximin in case of an emergency. The study medication, Rifaximin, is FDA-approved for the treatment of traveler’s diarrhea and some other conditions, but has not been approved to treat SIBO. Preliminary studies suggest treatment of SIBO may have an effect on PD symptoms.


You Are Being Asked To Take Part In This Research Study Because As Part Of Your Pd Treatment With Carbidopa/Levodopa (Sinemet), You Have Experienced Motor Fluctuations. Motor Fluctuations Means That During The Day You Have Some Periods When Your Symptoms Are Well Controlled (“On” Time), And Some Periods Where Your Symptoms Are Not Well-Controlled (“Off” Time).


Small Intestinal Bacterial Overgrowth, Parkinson's Disease

For More Information:

Hilary Perez
(513) 558-0112

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