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I had the most interesting conversation years ago at a 4th of July BBQ.
I knew almost no one there, but I somehow found the one person I identified with most. There was a guy eating plain meat and a little fruit, and he made a comment about how miserable it is to be gluten, dairy, sugar, and alcohol-free. My husband overheard, they got talking, and he sent the guy my way.
We got onto the topic of an antibiotic so expensive you almost can’t believe the quote. We’d had similar experiences. Then we realized we were talking about the same antibiotic: rifaximin.
Here’s the kicker. This man was a doctor. A major Bay Area surgeon, brilliant, and progressively getting sicker by the day: major bloating, vomiting, reflux, pain. His doctors suspected SIBO, and he was learning about it in real time, the same way I once had to.
That night reminded me of something I come back to constantly: SIBO is affecting more and more people, and even a surgeon can be lost in it. So let me give you the clear, current guide I wish someone had handed both of us.
7 Things About SIBO from a surgeon
That night, standing in a backyard talking to a stranger who turned out to be a Bay Area surgeon, I came away with 7 things that still hold up years later.
1] Food matters, and most doctors don’t teach it.
He had never heard of FODMAPs. I had to explain what they were and how they connect to SIBO symptoms. A brilliant man, and the food piece still wasn’t on his radar. If you have SIBO, understanding FODMAPs is a genuinely useful tool for managing symptoms. More on that below.
2] SIBO and IBS are tangled together.
His view was that SIBO is, in a way, the form of IBS doctors can now name, test, and treat with an antibiotic. His warning stuck with me: without fixing the root, you’ll take round after round of rifaximin and still not be healed. I’ve found that to be true.
3] Some supplements genuinely help.
He swore by Iberogast, one his functional doctor had him taking. I owned a bottle I hadn’t opened (I’m a walking supplement cabinet, and I’d pared way back to only the essentials). His experience is a reminder that the right targeted SIBO supplements, guided by a provider, can be part of the picture.
4] Bone broth earns its reputation.
He’d just discovered its healing properties. I’ve been making my own since 2009 and believe deeply in what it can do for the gut lining.
5] SIBO usually has a trigger.
His major problems erupted right when big new life stressors did. That fits the pattern I see constantly: SIBO tends to surface after a major life event, a major surgery, or travel where you pick up a bug. For me, it was my freshman year of college, all three kinds of upheaval at once.
6] Our food supply is part of the story.
He’s a traditional Western surgeon whose thinking runs Western-meets-Eastern, and he believes our food is making us sick. I’ve watched people heal in remarkable ways just by changing what they eat.
7] The emotional weight is real.
In his worst moments, he told his wife, “I will die from this.” Neither of us had a terminal diagnosis, but the limitations felt debilitating and the fear was real. The emotional side of chronic gut illness is one of the least discussed and most important parts of it.
Those 7 things are the human version. Here’s the clear, current guide to what’s actually going on.
What is SIBO?
SIBO stands for small intestinal bacterial overgrowth.
Your small intestine is supposed to have relatively few bacteria compared to your large intestine. SIBO is what happens when bacteria that belong further down your digestive tract overgrow in the small intestine, where they don’t belong in those numbers.
When that happens, those bacteria ferment the carbohydrates you eat before your body can properly absorb them. That fermentation produces gas (hydrogen, methane, or hydrogen sulfide), and that gas is what drives the hallmark symptoms: bloating, pain, and altered bowel habits.
There’s a related condition worth naming here, because the science has sharpened since I first wrote this. When the overgrowth is dominated by methane-producing organisms (which are technically archaea, not bacteria), it’s now called intestinal methanogen overgrowth, or IMO, rather than “methane SIBO.” IMO is strongly tied to constipation.1
SIBO symptoms
SIBO symptoms are real, disruptive, and often dismissed. They can include:
Bloating that often worsens as the day goes on. Excessive gas. Abdominal pain or discomfort. Diarrhea, constipation, or a mix of both. Reflux. Nausea. New food intolerances. And in some cases, nutrient deficiencies or unintended weight changes.
Make note: these symptoms overlap heavily with IBS, and with plain food intolerance, which is exactly why SIBO gets missed or mislabeled so often. Symptoms alone can’t confirm SIBO.
Is SIBO the same as IBS?
This is the question the surgeon and I kept circling, and his framing stuck with me.
His view: SIBO is, in a sense, a form of IBS, but it’s the form doctors can now name, test for, and treat with an antibiotic. His warning was the part that mattered most. “Without fixing the root of the problem,” he said, “you’ll take round after round of rifaximin and you will not be healed.”
He was right. SIBO has a specific name, a diagnostic test, and antibiotic (or herbal) treatments. But underneath, it often behaves like a chronic, relapsing condition that you manage at the root: motility, diet, stress, and the underlying cause. An antibiotic that kills the overgrowth doesn’t fix why the overgrowth happened.
What causes SIBO?
SIBO isn’t random. It usually traces back to something that let bacteria accumulate in the small intestine. Common contributors include:
Impaired motility. This is the big one for me personally. Your small intestine has a housekeeping wave called the migrating motor complex (MMC) that sweeps leftover food and bacteria through between meals. When that stalls, bacteria linger and overgrow.
A triggering event. In my experience, SIBO often surfaces after one of three things: a major life stressor, a major surgery, or travel outside the country where you pick up a bug. For me, it was my freshman year of college: the end of a devastating relationship, being away from family for the first time, and an illness that knocked me out for two weeks. I was never quite the same after.
Low stomach acid, structural issues, prior abdominal surgery, and certain medications can also set the stage.
The surgeon and I agreed on something bigger, too: he believed our food supply is making people sick, and I’ve watched people heal in remarkable ways just by changing what they eat. That’s not the whole story of SIBO, but it’s part of the terrain.
How is SIBO tested?
Here’s where I’ve updated this guide most, because the guidance genuinely changed after 2016.
The most common test is a breath test. You drink a measured sugar (glucose or lactulose), then breath samples are collected over about 2 hours to measure the gases the microbes produce.
Per the North American Consensus (2017) and the American College of Gastroenterology guideline (2020), the current standards are:12
A rise in hydrogen of 20 ppm or more by 90 minutes is considered positive for SIBO. A methane level of 10 ppm or more at any point is considered positive for methanogen overgrowth (IMO). Consensus substrate doses are 75g glucose or 10g lactulose, with lactulose often favored in certain patients.
There’s also a more invasive option: a culture of fluid taken from the small intestine during endoscopy. The threshold that defines a positive culture was lowered in recent years to 10³ colony-forming units per milliliter, down from the older 10⁵ figure.2
Make note: breath testing is imperfect and results should always be read alongside your symptoms, history, and other possible diagnoses, not in isolation. The ACG guideline itself frames breath testing as a conditional recommendation, which is the honest state of the evidence.2
Get my in-depth guide to all things SIBO + healing it.
How is SIBO treated?
Treatment usually has two parts: reduce the overgrowth, then address why it happened.
Reducing the overgrowth. This is typically an antibiotic (rifaximin is the most associated with SIBO) or an herbal antimicrobial protocol. Some people need more than one round.
Addressing the root. This is the part the surgeon warned me about, and the part most people skip. It can include motility support (prokinetics, meal spacing), managing stress, supporting stomach acid, and using diet strategically.
Diet’s role. A low-FODMAP approach is a common tool for managing symptoms, because FODMAPs are the fermentable carbs that feed the overgrowth. But I want to be clear, the same way I am everywhere on this site: elimination is a short-term tool, not a permanent way to live. Food triggers symptoms; the underlying dysfunction causes them.
The surgeon, for what it’s worth, had never heard of FODMAPs. A brilliant man, and the food piece still wasn’t on his radar. If you have SIBO, understanding FODMAPs is a genuinely useful part of managing symptoms while you work on the root.
The emotional side of SIBO
I won’t end on testing thresholds, because that’s not the whole truth of this illness.
That night, the surgeon told me that in his worst moments of vomiting and misery, he’d told his wife, “I will die from this.” I didn’t believe that was true, and I don’t think he fully did either. But I understood the feeling completely.
We hadn’t been diagnosed with a terminal illness. And yet the limitations felt debilitating, and the fear was real. The emotional weight of a chronic gut condition is one of the least talked about and most important parts of it. If that’s where you are right now, you’re not being dramatic, and you’re not alone.
What I know now, in remission
When I first wrote this, I said there’s no cure and no magic formula, and that a relapse can happen at any time. That caused some pushback in the comments, and I understand why. Nobody wants to hear it.
Here’s where I’ve landed after years of living it: “cure” and “long-term remission” aren’t the same word, and remission is absolutely possible. I’ve been in it since 2018. It took addressing my motility, stomach acid, and stress markers, not just killing bacteria round after round. The sum of the parts is greater than any single action taken in isolation.
If you’re at the beginning of this, take heart. It’s hard, but it’s navigable, and you don’t have to figure it out alone.
Not sure where you land or what to do first? Take the quiz and I’ll point you to the next right step. If you kind of already know where you land, read through the Structured Gut Method.
| Term | What it means |
|---|---|
| SIBO | Small intestinal bacterial overgrowth. Too many bacteria in the small intestine, where there should be relatively few. Causes bloating, gas, pain, and altered bowel habits. |
| IMO | Intestinal methanogen overgrowth. An overgrowth of methane-producing archaea (not technically bacteria), strongly linked to constipation. Formerly loosely called “methane SIBO.” |
| MMC | Migrating motor complex. The “housekeeping” waves that sweep leftover food and bacteria through the small intestine between meals. Impaired MMC is a common driver of recurrent SIBO. |
| Hydrogen SIBO | Overgrowth producing mostly hydrogen gas, more often associated with diarrhea. A breath-test hydrogen rise of ≥20 ppm by 90 minutes is considered positive. |
| Methane (IMO) | Methane ≥10 ppm on a breath test is considered positive for methanogen overgrowth, more often associated with constipation. |
| Rifaximin | The antibiotic most associated with SIBO treatment. Reduces the overgrowth but doesn’t address the root cause on its own. |
SIBO FAQ
What is SIBO in simple terms?
SIBO is small intestinal bacterial overgrowth: too many bacteria in the small intestine, where there should be relatively few. Those bacteria ferment your food too early, producing gas that causes bloating, pain, and changes in your bowel habits.
Is SIBO the same as IBS?
Not exactly, but they overlap heavily. Many people diagnosed with IBS actually have SIBO underneath. The difference is that SIBO can be tested for and treated directly, though lasting relief still depends on addressing the root cause.
How is SIBO diagnosed?
Most commonly with a breath test using glucose or lactulose, measuring hydrogen and methane over about 2 hours. A hydrogen rise of 20 ppm or more by 90 minutes, or methane of 10 ppm or more, is considered positive. Results should be read alongside your symptoms and history.
Can SIBO be cured?
“Cure” and “long-term remission” aren’t the same thing. SIBO can relapse, especially if the root cause (often motility) isn’t addressed. But lasting remission is absolutely possible. I’ve been in it since 2018.
Why does SIBO keep coming back?
Usually because the underlying cause wasn’t addressed. For many people, including me, that’s impaired motility (a stalled migrating motor complex). Killing the bacteria without fixing why they overgrew tends to lead to relapse.
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Xox,
SKH
Sarah I am literally in tears reading this because I feel like I am finally not alone. I was just diagnosed with SIBO on Thursday and am on my 2nd day of Xifaxan. I am still at a loss as to where I even go from here. As a allergy food blogger I feel like I should know how to heal myself but here I am, wondering the the heck I can even eat that won’t make me feel like I want to die. I probably am sounding so incredibly dramatic right now but it is such a relief to read the information you shared. I would love to connect with you further if you have a few minutes to spare ( I know it is hard to come by). Thank you so much for posting this.
Hi, Annmarie! First of all…lots of hugs. You will get through it. Second, peruse my site. I have written a TON about SIBO. As you are only on your 2nd day of Xifaxan, my biggest piece of advice would be to make sure you are eating FODMAPs while on the antibiotic (at least to the point you can handle them). I’m not sure how long you’ll be on the antibiotic, but do know that it was never until Day 14 when I took a drastic turn for the better. Read this post – You Must Live Life –> http://bit.ly/skhlife Hang in there!
Yeah they all throw us into the IBS bin, the G.I. centers they want to prescribe and cut too, I learned that the hard way when they groupthinked me into cutting a healthy organ out of my body, health got worse, and I was isolated when I needed help more than ever and yes I thought I was dying for about a year afterwards. Surgeons won’t know anything about general health, they might if they have an interest but they are trained in cutting. Half the battle with bone broth is sourcing healthy bones as bones are a lead/heavy metal sink. The stress trigger regarding surgery is right on, since hospital acquired infections are incredibly common, if they even open you up they are giving you intravenous antibiotics to protect themselves as iatrogenic disease is the third leading cause of death in the U.S. The antibiotics change your microbiome and your often worse off coming out of the hospital in more ways than one. Fodmaps .. I had emu, zuchini, and two heads/bulbs of garlic I grew myself here for lunch, I’ll be fine until this food gets into my lower intestine then I will pay, but I’m not wasting all this good fresh potent garlic
All great thoughts. Thanks for stopping by, and for sharing more practical experience with SIBO.
Hi I just found your blog and soo excited to read all the good info! I am on my 2nd round of rifaximin the first being 550mg twice a day for a month. Couldn’t believe what j could eat while on them but when it was time to stop my Ibs attacks were 10x worse then when I started but within a few weeks they calmed down. That was 2 months ago and now back where I started and taking them again! I don’t want to live a life where I can’t eat! There is nothing that I can eat that tastes good as I have always been a very picky eater! I am sure I will relapse again cause I can’t not eat carbs or become extremely light headed. Is going on the meds often a bad thing! And why would my Ibs get worse after stopping?? Thx
Hi, Barb! So happy you found my blog. To answer your questions…some (even most) people need 2, 3 or even more rounds of the antibiotic to help clear it up. That said, your IBS got worse because you didn’t address the underlying issue. For me, my SIBO relapses when motility comes to a halt. I do several things to keep things moving these days. I hope you find your underlying issue, and that you are able to appropriately address it.
This was tough for me to read. I was just diagnosed with SIBO a week ago after 5 years of suffering with no answers. I’m also 9 weeks pregnant and have a 3 year old and a 1 1/2 year old. I am currently suffering through the worst flare-up of my life to the point that I can hardly get off the couch. I can’t do a single thing to treat it until I’m finished with the pregnancy AND nursing. I have been entrenched in online research, desperate to hear stories of people who have beat this for good but have found very little. “There is no cure” just killed me. I feel like I’ve been diagnosed with a terminal illness and I’m having a difficult time wrapping my mind around the fact that my life will never be the same. I’m sure my pregnancy hormones are making this whole thing so much worse, but I’m feeling so absolutely defeated.
Hi, Anna! I am so sorry to hear all of this, but TRUST ME, I get where you are and how you feel. I feel like I am about to relapse. I have a 3-year-old, 17-month-old and 5 month old. It. Is. Hard. I realize that a lot of people were upset when I said there is no cure. I never wanted to believe it until the doctor went over it in detail with me. I DO believe 1,000% percent that you can go into remission on it for a very long time, even for life, but I also know that that’s really hard to do for many people. I have taken the antibiotic 3 times now, and I vowed I would not take it again for at least a year. The good news is that I know exactly how to get it under control with diet and lifestyle. The bad news is that it’s really, really hard. I wish you peace with it. Hang in there. My website will always be here for love and support. xo
“There is no cure” is not true. SIBO IS treatable. It can be eradicated. I’m working with a holistic doctor currently and we will beat this misery. Please don’t say there is no cure.
But a cure and treatable are not the same things. Also, I didn’t say it. The doctor did. I’ve lived almost 2 years trying to “cure.” When you have cured, then let me know. To know me is to know I aim NOT to depress. I am an optimist but a realist. I wish you well.
Sarah and to all in the feed above. I’ve been dealing with endless tests, chronic fatigue and countless symptoms for over 2 years. Just last night I ended up in the ER again because of dehydration from constant vomiting over the weekend. Last week, the PA at my GI’s office tested me for SIBO and I came up positive (on top of IBS-C). I am at a loss what to eat…my stomach is so upset that eating some of the foods on the HFLC diet I was given just seem horrible when I’m already throwing up. The ER doctors last night had no idea what SIBO was and could offer little help. I have been beginning to think I was crazy until I read this page. I’m interested into why my Dr prescribed me plain old amoxicillin -which I haven’t been able to keep down. Thank you all for sharing your experiences and to Sarah for creating this page. I’d love more information if anyone can share. I’m finding it hard to find relevant and good content online. My regular doctor practices both functional and some holistic practices, do you think I would get better results going the holistic way? My daughter has Celiac’s so we are used to “special” diets and lifestyles that insist on a healthy eating, but this one has me really blown away. Please any tips of where to start would be amazing. Glad I found this page.
Hi, Grace! Thank you for stopping by. I am so sorry for all your pain. Are you low FODMAP currently?
I was on low FODMAP and they told me to switch to High Fat Low Carb (and for the next 3 weeks eliminate all sugars and grains). It seems like this is a very new type of diagnosis and a lot of people don’t really have expertise in what to do. This HFLC diet is much more restrictive on some ends then the FODMAP so that’s why I’m having a hard time. Just eating meats, fruits, and veggies, but with an upset tummy, that’s hard to do. Hoping it will start turning around. I’m just thankful to come across your blog already. I fell like I’m going crazy 🙂
Start here, if you haven’t read this post yet -> http://bit.ly/skh2017ss And then -> http://bit.ly/skhmssibo 🙂
Hey Sarah, thank you for your information. I have been struggling for a couple of years and was diagnosed with SIBO last week. I am now on a regiment of the antibiotic. I am so happy I found your blog and look forward to learning more.
You are most welcome, Sharon. Let’s hope the antibiotic clears it up right away!
So curious to hear how you go with Iberogast stuff.. my functional therapist literally has no idea what’s going on after many tests and has said here take this and I haven’t heard from her since 🤦🏼♀️ Exceptionally infuriating.
Needless to say I’ll keep trying to work out my gut issues on my own.
But yes a post on your progress with Iberogast would be good to hear if you’re down 🙂
I’m doing phenomenal! If you read my latest posts, you’ll see it all:)
What a great article ! I was diagnosed last August w/sibo. Battling almost a year. 3 rounds Abxs.. oregano , peppermint then garlic , digestive enzymes and MMC select(similar to ibergast) .. and had to slowly slowly work up to a soil based probiotic (all others made it worse). Watch my die()also just cut out eggs and butter)also started celery juice last few weeks and felt the die off symptoms . Have my ups and downs . I just try to manage it . I am having better days but then I flared when I drank some wine! Felt like death after so no more alcohol . I also went out of the country and then dealt with hard break up.. I’m convinced that started this all. Thanks for all of your info!
Hi Michele – Welcome to the community. Yes, both going out of the country and the stress from a hard break up can be triggering points. Hang in there….xox
I am so so happy i came across this post. I am about 6 weeks pregnant now and was diagnosed with SIBO 5 days prior to us finding out. Cant take the antibiotic now. I was in the ER with the WORST flare up and at first my GI doc tried to insinuate that this was probably pregnancy related. Absolutely NOT. This is no “morning sickness” so what did you take or do during pregnancy? I am so lost and no idea what to do…