Does your gut need a reset?

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Do you want to start feeling better?

Yes, Where Do I Start?

Do you want to start feeling better?

Yes, Where Do I Start?

Resetting the Microbiota of the Small Intestine

Increased diversity of the intestinal microbiota (world of bacteria) generally appears to be a good thing. Can we achieve increased diversity by administering agents that kill bacteria? Can antibiotics or antimicrobial herbs increase diversity? Let’s discuss an important but often overlooked concept.

Dr. R’s Fast Facts

Resetting the Microbiota with Rifaximin as it Relates to SIBO (Small Intestinal Bacterial Overgrowth)

How Does Rifaximin Help Treat or Reset the Microbiota?

  • By administering an antibiotic like Rifaximin you may be able to increase the diversity in your small intestine.
    • The job of Rifaximin (along with other herbal antimicrobials) is to limit the “bad guys” (bad bacteria that is overgrown) allowing the “good guys” (helpful bacteria) to grow, thus increasing your diversity.
  • While it may seem to make sense to increase diversity in the gut by adding Prebiotics and Fiber to your regimen, for many people with SIBO, this makes the symptoms worse.

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Resetting the Microbiota of the Small Intestine

Dr. Michael Ruscio: Resetting the small intestinal microbiota with rifaximin. Hi, this is Dr. Ruscio, and you’ve likely heard of SIBO, or small intestinal bacterial overgrowth, which can oftentimes manifest as the symptoms of IBS—gas, bloating, constipation, diarrhea, loose stools, abdominal pain. In fact, in some cases, the majority of IBS may be caused by this SIBO, this small intestinal bacterial overgrowth, and there is an antibiotic called rifaximin that has been shown to be very effective in treating this small intestinal bacterial overgrowth.

Recently a paper was published discussing an interesting concept in how rifaximin helps to treat this bacterial overgrowth in the small intestine, and what it may actually do is allow the small intestinal microbiota to reset. Now, allow me to expand on exactly what that means. In small intestinal bacterial overgrowth, of course, you have too much growth of bacteria in the small intestine. When you have an overgrowth, what can happen is one group of bacteria can change the environment in such a way that it crowds out other bacteria, and this can have a negative effect on the whole bacterial colony.

One of the things that is often recommended that we try to do is increase the diversity of the microbiota, and while not all data are consistent on this, there does seem to be a general trend that more diversity—more types of trees and life, to use a forest analogy—in your intestinal bacteria is healthy. Because we’re observing this, oftentimes the recommendation is to reach for things like fiber and prebiotics that increase diversity. Now, this is not necessarily a bad idea, but in some cases it can be a bad idea because, you see, if you do have small intestinal bacterial overgrowth, there’s a chance that fiber and prebiotics will actually make you worse.

But—and here’s where rifaximin ties into this picture—if we can remove or kill off the overgrowth of bacteria, that changes the environment in the small intestine and allows the other populations that were dwindling to grow, thus increasing your diversity. So while it sounds a little bit counterintuitive, by administering an antibiotic or an herb that has antimicrobial activity, you may actually be able to increase the diversity in your small intestine because you’re going to limit the bad guys that are pushing out the other good guys, allow the good guys to grow, and thus increase your diversity.

This is an interesting concept I wanted to introduce especially because sometimes with the microbiota literature we get a little bit confused in terms of how to arrive at the increased diversity. What I’ve seen clinically is that more often than not, interventions that tend to get rid of bacteria that shouldn’t be there tend to cause patients to feel the best. Part of what may be happening underneath the surface there is they are actually increasing their microbiotal diversity and thus healing their gut, even though they’re increasing their diversity using something that actually kills bacteria. It sounds counterintuitive, but it seems to be a very sound clinical treatment.

Anyway, this is Dr. Ruscio, and hopefully this information helps you get healthy and get back to your life. Thanks.

What do you think? I would like to hear your thoughts or experience with this.

Dr. Ruscio is your leading functional and integrative doctor specializing in gut related disorders such as SIBO, leaky gut, Celiac, IBS and in thyroid disorders such as hypothyroid and hyperthyroid. For more information on how to become a patient, please contact our office. Serving the San Francisco bay area and distance patients via phone and Skype.


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