The SIBO Saga: Part 1

Disclaimer:  As I have said in the past, I’m not a research blogger.  I’m here to mix “data with soul” and give you useful info, but only in the context of my real, human experience.  That is not to say that citation on my part and proper follow-up on your part are not important.  Everything I wrote about in this blog was presented by Dr. Mark Pimentel and Dr. Alison Siebecker at the SIBO Symposium during January 2014 and you can pay to have access to those presentations through the National College of Natural Medicine’s website.  

Friends . . . for real . . . the SIBO Symposium hosted through the National College of Natural Medicine in Portland, Oregan this past January was mind blowing.  I have been promising to write about it for almost two months.  Why so long, Angie?  Get on it already!

Honestly, there was so, so much information, most of which I had never learned before (and I have spent a ton of time learning about SIBO, so this is saying something), that I just simply could not distill it all and competently write about it.  I’ve decided the best way to handle that is to go back and slowly rewatch each video from the two days of presentations, reread all my notes (and take more) and re-review all the handouts and THEN write a series about each topic within the broader SIBO subject.  Today I’m going to write about Methane-Dominant SIBO.  (Also, weird topics I never expected to be interested in during my lifetime:  Methane-Dominant SIBO.  So just want to mention that!)

Okay, so I have posted on my Facebook page before about the two kinds of organisms that lead to SIBO (btw, if you are reading this & still don’t know, SIBO stands for Small Intestine Bacterial Overgrowth):  hydrogen producers and methane producers.  Hydrogen producers lead to SIBO with diarrhea and methane producers lead to SIBO with constipation.  The dominance of either gas is detected during a Lactulose Breath Test, where a patient drinks a sugary solution that the organisms ferment.  The patient then blows these gases out into a small baggy and that captured air is measured by a machine.  This is why it is so important for you to learn about the gas measurement results from your breath test, should you have one performed to detect SIBO.

Notice that in the past I have always referred to these organisms as bacteria & the name SIBO itself implies bacteria only, but according to one of the presenters at the symposium, Dr. Mark Pimentel, the pre-dominant methane producing organism in humans is NOT a bacteria.  It is called Methanobrevibacter smithii or M. smithii and is an archaea.  This organism, M. smithii, is responsible for the constipation associated with Methane-Dominant SIBO, because methane changes our intestinal muscle motor function.

As you might have guessed, treatment for SIBO changes depending on whether or not you have diarrhea or constipation.  Unfortunately, treatment for SIBO with constipation is tougher, this is because there are not specific drugs developed to deal with the methane producing M. smithii.  The absolute best, hands down most effective antibiotic for SIBO is called Rifaximin (also called Xifaxan).  It knocks out the overgrowth, but it is also mostly absorbed in the intestine so it is not as damaging system wide as other antibiotics.  However, Rifaximin alone will not work on the methane organisms.  It is best to combine Rifaximin with another antibiotic, called Metronidazole, when treating SIBO with constipation.

This was a very interesting piece of information for me, because my personal experience with SIBO with constipation definitely confirms this to be true.  The first time I was treated for SIBO, I was given Metronidazole.  It was very hard on me emotionally, with each dose reducing me to tears (gut-brain connection, people!), but it worked very well.  I had relief right away and despite not being on a low FODMAP diet, I didn’t have any trouble with SIBO again for nearly a year.  Then I had retesting and the lactulose solution sparked a resurgence in the SIBO (I am actually not a fan of retesting for this reason).  This time, my doctor only prescribed Rifaximin (after an herbal antibiotic attempt, more on that later) and it didn’t work as well.  I had symptoms again within a short period of ending the treatment.  Thankfully they were mild enough that I brought them under control with a low FODMAP approach.

Another good option, according to Dr. Pimentel, is an antibiotic called Neomycin combined with Rifaximin.  Occasionally, insurance providers will not cover Rifaximin for SIBO treatment.  This is because Rifaximin is normally used to treat people with Hepatic Encephalopathy, which is a liver disease that is effecting the brain.  In those cases, a combination of Metronidazole and Neomycin may be the best option for treating either kind of SIBO, diarrhea or constipation.

There is also another situation that can sometimes occur with SIBO.  A patient comes back with a breath test that does not show high levels of methane, but they are reporting constipation.  Remember, constipation goes with high methane.  Based on Dr. Pimentel’s presentation, this is because occasionally there is enough methane being produced by M. smithii to slow motor function, but not enough to be detected in the breath test.  The breath test is not sensitive enough to detect parts per billion, only parts per million.  If this is the case, the patient might be treated with Rifaximin, but it does not work since Rifaximin alone can’t deal with methane producing organisms.  Again, I think this means you need to be aware of your exact breath test results, but you should also be forward with your doctor about your symptoms.

Another reason that Methane-Dominant SIBO (SIBO with constipation) is so tough to treat, is that these organisms come back more quickly following a course of antibiotics.  This is where following a low FODMAP diet comes into play.  It is very important with this kind of SIBO to remain low FODMAP for a period of time following medication, in order to starve any of the remaining organisms that did not die off during antibiotic treatment.

Since we are talking about diet, I think it is also important to note here that according to one of the other presenters (and my SIBO heroine), Dr. Alison Siebecker, diet alone will NOT treat SIBO in adults.  In the Autoimmune Paleo community we tend to be very, very careful about antibiotic use and even approach it with alot of skepticism.  That is a good attitude, since for many of us, overuse of antibiotics may be in part to blame for our predicament, but there are appropriate times to use them.  I believe SIBO is one of those times.

That was the meat of the presentation relating to Methane-Dominant SIBO.  I will be writing about Hydrogen-Dominant SIBO, Herbal Antibiotics, Diet for SIBO, and also hopefully other health issues that are connected with SIBO in the coming weeks, so stay tuned.  There is alot to cover, but I think it is worth it, since SIBO & AI often seem to go hand-in-hand.  I’m going to do my best to provide great deets for you guys!

You can find Part 2 of the SIBO series here.

About Angie Alt

Angie Alt is part of the blogging duo behind Autoimmune Paleo. She helps others take charge of their health the same way she took charge of her own after suffering with Celiac and other autoimmune diseases; one creative, nutritious meal at a time. Her special focus is on mixing “data with soul” by looking at the honest heart of the autoimmune journey (which sometimes includes curse words). She’s also a world traveler who has been medically evacuated from two foreign countries. Strategizing worst-case scenarios is now something of a hobby. She is a Certified Health Coach through the Institute for Integrative Nutrition and author of The Alternative Autoimmune Cookbook: Eating for All Phases of the Paleo Autoimmune Protocol. You can also find her on Instagram.


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