SIBO (Small Intestinal Bacterial Overgrowth) can be a frustrating and often confusing condition. There are multiple options for treating it and managing the symptoms, and some may work better for you than others.
In this post, I’ll be jumping into more detail about the most common treatments for SIBO, as well as the pluses and minuses of each. [If you want to back up and learn more about what SIBO is and how you could have gotten it, check out this previous post].
First off, I want to point out that this post is purely informational, I strongly advise working with a qualified practitioner to help you navigate treatment.
Next, I want to address that there are three different types of SIBO, differentiated by the main types of gas produced by the bacterial overgrowth in the small intestine.
Each type of SIBO has its own issues and complications. Certain treatments may be more effective for different types, which is why I think it’s important to go over them.
Hydrogen Dominant (SIBO-D)
If you have SIBO with diarrhea (SIBO-D), you’re likely suffering from an overgrowth of hydrogen-producing bacteria in the small intestine.
Bacteria produce hydrogen gas as a byproduct of carbohydrate fermentation in the digestive system. This is a totally normal process, and hydrogen does exist in our large intestine as a byproduct of this fermentation. It’s when large amounts of hydrogen gas are produced in the small intestine that we start to have a problem. This excess hydrogen tends to cause fast transit time and/or loose stools.
Methane Dominant (SIBO-C)
Along with bacteria, our intestinal flora is also comprised of organisms known as archaea. Archaea are actually different than bacteria - they’re single-celled organisms that don’t have a nucleus.
Archaea in our digestive system feed off of hydrogen that bacteria produce during the fermentation of carbohydrates (fiber specifically). Archaea then produce methane as a byproduct of their digestion.
The more fermentation of fiber and hydrogen gas that occurs in the intestines, the more methane the archaea will end up producing.
Lactose malabsorption and decreased motility of the digestive tract have been correlated with an overgrowth of archaea in the gut. This can also lead to constipation and excessive bloating.
Hydrogen Sulfide Dominant
This is the most recently discovered type of SIBO and the research about how to test for and treat this type is still in its relative infancy.
The human body uses sulfur for our cells and microbiome, and detoxes and excretes most of the byproducts of sulfur metabolism that it doesn’t need.
In a healthy person, small amounts of sulfur is converted into hydrogen sulfide.
One telling symptom of hydrogen sulfide SIBO is gas that smells like rotten eggs (I know, yikes).
This one can be tricky, because we don’t currently have a way of testing for it. The breath tests that are available to the public right now only test for hydrogen or methane.
So if you get a negative test result, but are still experiencing symptoms, this could be why. There are a few telltale markers on a breath test that could point to hydrogen sulfide, so be sure to work with a qualified practitioner who is up to date on the latest research and can help figure out if this could be the case for you.
What Do I Do About It?
Ok now we’ve covered the three types, so what do we do about them? How do you try to get rid of SIBO so you can go back to living a healthy, normal life?
The three main ways to address SIBO are:
AntibioticsOne way to deal with bacterial overgrowth in the small intestine is to kill it with antibiotics which inhibit/kill the bacteria in the small intestine.
Rifaximin (aka Xifaxan) is the main antibiotic used to treat SIBO. What makes Rifaximin different from other antibiotics is that it is non-systemic, meaning that it stays in the small intestine and doesn’t get absorbed into the bloodstream.
When treating SIBO-C, practitioners typically combine Rifaximin with another antibiotic, like Metronidazole or Neomycin, which increase the ability to kill off methane-producing organisms.
Pros of Rifaximin
Lots of research to back it up.
Fewer side effects than regular antibiotics since it stays localized to the small intestine.
Can actually have a “eubiotic” effect in the digestive system (meaning it can promote the growth of healthy bacteria).
Can reduce intestinal mucosal inflammation [which can cause many IBS-like symptoms on its own].
Very expensive. It can be as much as $1,500 when not covered by insurance, and sometimes insurance companies don’t want to cover it for various reasons.
Relapse rate is relatively high. Studies show SIBO recurs in almost half of patients within 1 year of treatment. This is most likely because the underlying root cause was not addressed.
Rifaximin isn’t as effective in constipation or hydrogen sulfide cases and needs to be combined with other antibiotics (see above).
AntimicrobialsThis is the option that people normally choose if they’re looking to go a more natural route. Combinations of herbs or herbal extracts with antimicrobial effects are taken for 4-6 weeks (depending on the practitioner).
Atrantil is another natural product that has been generating some buzz lately. The consensus seems to be that it’s more effectivein methane-dominant SIBO (SIBO-C) cases.
Commonly used formulations include:
The most commonly used ones are:
Allicin (from garlic)
Made from whole plants, so they contain many different beneficial compounds.
Many different compounds that exist in the plant material can work in synergy to treat resistant organisms.
Easy to access. No prescription needed, most can be bought online.
Can also be expensive. Even though they are less $ than conventional antibiotics, you need to take them for a longer period of time, so the total cost can add up.
Are not as precisely targeted as Rifaximin, meaning if taken long-term, they can have a negative effect on the flora of the large intestine.
May need to try several different combinations before you find one that’s effective for your case. May also need to do multiple rounds.
Elemental DietThe Elemental Diet is used to treat SIBO by starving the bacteria while continuing to feed the person. It works by replacing meals for 2-3 weeks with an Elemental formula. Elemental formula is essentially powdered nutrients that come in a pre-digested form.They contain protein as amino acids, carbohydrate as glucose or maltodextrin, fat as oils, and vitamins & minerals. You can buy a pre-made version or make your own at home from ingredients purchased online.
Very effective. Shows 80-84% success rate in eradicating SIBO.
Can reduce need for multiple rounds of antibiotics or antimicrobials. A 2 week course can reduce high gas more quickly than any other treatment.
Most people can tolerate it. I.e. some people may have adverse reactions to certain herbs or antibiotics, but most people handle the ED well.
Works very quickly.
Easy to obtain. Most brands are available online, though Physicians Formula needs to be purchased through a practitioner. [I have an online dispensary that stocks this product. Contact me for details.]
Can be expensive.
Taste of many formulas (especially homemade) can be hard to tolerate. The general consensus is that the Physicians Formula is the best-tasting formulation.
Can be challenging to stick to. Not eating solid food for two weeks can be boring and hard for many people.
Most formulations are high in sugar. This can lead to yeast overgrowth, so many people recommend taking an antifungal at the same time (Nystatin is a popular one prescribed by many doctors).
Addressing The Underlying Cause
In addition to treatment, the underlying cause of the SIBO must to be addressed in order to prevent relapse, which can be very common.
I won’t go into detail on all of the underlying causes in this post, but I want to talk about the Migrating Motor Complex (MMC). The MMC is a wave of electromechanical activity that sweeps through the small intestine every few hours to sweep any undigested food or bacteria down into the large intestine. If it gets damaged (which commonly happens with food poisoning), bacteria can stick around in the small intestine, leading to SIBO.
One way to help restore the function of the MMC is the use of prokinetics, which are drugs or herbal compounds that help with gastrointestinal motility. After treatment, prokinetics are typically used for 3 months or more.
Popular prokinetics include:
Low dose erythromycin
Another thing worth mentioning about the MMC is that the sweeping wave only happens when we are in a fasted state - AKA when we stop eating for a while. Due to this, the best practice is to leave at least 4-5 hours between meals if possible and to not snack between meals.
This gives the MMC a chance to sweep through your digestive system, clearing out any bacteria that shouldn’t be there. If you don’t stop eating long enough for it to activate, you can run into trouble or risk relapse.
So what do I eat?
While treatment is important, sometimes symptoms can remain. This can be frustrating, so in addition to treatment, some sort of modified diet can be very useful to help manage those symptoms.
It’s important to note that other than the Elemental Diet, there is no diet that can treat or cure SIBO. Special diets are mainly for managing symptoms.
The most common diets people find helpful are:
FODMAPs are certain types of carbohydrates that are more likely to ferment in the digestive system, feed bacteria, and cause gas and bloating. Avoiding these foods for a period of time after treatment and while healing can be helpful for managing symptoms. If you’re new to FODMAPs, a sample food list can be found here.
SCD, or the Specific Carbohydrate Diet, is a form of an elimination diet that removes many common carb sources, in order to prevent fermentation in the gut and facilitate healing of the digestive system. It restricts all grains, dairy products, many types of sugars, and most starches. This diet tends to work better on people with SIBO-D. More details and a food list can be found here.
Developed by “SIBO Queen” naturopath Dr. Allison Siebecker, the SIBO Specific Diet is her version of a combination of The Specific Carbohydrate Diet and the low FODMAP Diet. She has treated thousands of cases of SIBO, so the diet includes her clinical input and several alterations from the original diets, based on her experience. It combines the best of both diets, reducing a broader range of fermentable carbohydrates than any other SIBO diet. It also happens to be one of the most restrictive options. Because of this, it’s recommended to try the other less restrictive diets before this option. Details and a food list can be found here.
Everyone’s mileage will probably vary on different diets and it may take some playing around to find what works for you. Working with a practitioner can help you figure out which diet will work best for you and which foods you can and can’t tolerate.
And because a SIBO diet is not permanent, you may also need help with how to add those foods back in. Once SIBO has been eradicated and the gut has been given the opportunity to heal, the goal is to resume eating as wide and varied a diet as possible.
The Wrap Up
SIBO can be a uniquely complicated and frustrating condition. I know from personal experience that it can be a lengthy journey. It’s a tough diagnosis, but it is possible to heal and go back to living a normal life.
This blog post just scratches the surface, so I strongly encourage you to work with a qualified practitioner, and don’t get discouraged.
Any questions? Leave 'em in the comments.
Have SIBO and want to chat about your options or need help navigating the different diets? Schedule a free 15 min chat.
If you've been diagnosed with or treated for SIBO and aren't sure what to eat, download my free 5 Day SIBO Meal Plan + Recipe Guide here.