Small intestinal bacterial overgrowth (SIBO) is a digestive condition featuring an overgrowth of gut microbes. It can greatly affect someone’s quality of life and lead to mental health conditions like anxiety and depression. Symptom management is crucial for helping people with SIBO to live their best lives. Yet, a phenomenon called SIBO die-off prevents many people from starting treatment. Die-off can worsen symptoms before they show improvement. SIBO die-off symptoms are not as bad as people think. They are temporary and will improve. For many people, going through this phase is the only way to become free of SIBO symptoms once and for all.
When do SIBO die-off symptoms start, why do they happen, and how long do they last? We answer these questions and many more in this guide, so read on to find out.
Expert Opinion
In many circumstances, practitioners may try to distinguish between the different types of SIBO using a variety of tests. Here at Revolution Gut Health, we believe that regardless of the type of SIBO, the protocol for improving symptoms begins with the same foundation; improving the terrain conditions by removing environmental toxins, along with supporting the function of the support organs like the liver and kidneys. We believe that by doing so, we will achieve a balanced state of the GUT where your living microbes will thrive according to this healthy terain that is given by using our suggested protocols.
How Do I Know If I Have SIBO?
You know you have SIBO if you experience persistent digestive symptoms and test positive on a breath test, small intestinal aspirate and culture, or urinalysis. The symptoms of SIBO vary by type but may include:
- Diarrhea
- Constipation
- Bloating
- Stomach pain
- Excessive gas
- Nausea
Certain types of SIBO can cause downstream effects if left untreated. For example, hydrogen SIBO primarily causes diarrhea, which may lead to dehydration and/or malnutrition down the line.
Unexplained weight changes may indicate all three types of SIBO. Untreated methane SIBO is associated with weight gain. Untreated hydrogen sulfide and hydrogen SIBO may lead to weight loss.
Hydrogen sulfide can be the most dangerous type of SIBO if left untreated. It is a neurotoxin that can negatively affect the nervous system. Even low levels of hydrogen sulfide toxicity can cause headaches, insomnia, dizziness, and fatigue.
Revolution Gut Health offers testing services to help people understand which toxins contribute to their symptoms.
SIBO Treatment
SIBO treatments vary depending on the underlying cause, someone’s SIBO type, and whether the patient prefers natural or synthetic therapies. Regardless of how the SIBO gets addressed, the goal is to control the person’s symptoms, eliminate the overgrowth, and restore balance to the gut.
Sometimes, doctors can identify the underlying cause (e.g., low stomach acid). In this case, addressing the health issue first may lead to symptom relief.
Antibiotics are the most common synthetic remedy for SIBO. Rifaximin is the gold-standard antibiotic used for SIBO. In one study, this antibiotic had a 70.8% success rate for eradicating overgrown bacteria in the small intestine.
Natural ways of improvement can be just as effective, if not more effective, than rifaximin. Studies have compared the benefits of rifaximin to herbal antimicrobials for SIBO. One found that herbal remedies were 12% more effective than rifaximin for treating hydrogen SIBO.
Diet changes are another natural approach to managing SIBO symptoms. Some diets have even been studied as a cure for SIBO. Diets for SIBO include Low-FODMAP, Specific Carbohydrate, Low Fermentation, and Elemental Diets.
What Is SIBO Die-Off?
SIBO die-off is a collection of gut health symptoms that often occur during the initial phases of treatment. Though uncomfortable, they are a good sign that the overgrown bacteria causing someone’s symptoms are dying.
Why Does SIBO Die-Off Happen?
SIBO die-off happens because the overgrown microbes underlying the condition start to die off, sometimes creating uncomfortable symptoms. In hydrogen and hydrogen sulfide SIBO, these microbes are bacteria. Methane SIBO features an overgrowth of methanogens, a type of archaea.
More specifically, antibiotics and antimicrobials target microbes’ cell walls. They can puncture and rupture these cell walls, causing the cell’s innards to spill out. The innards consist of nutrients, toxins, and gases, among other things.
SIBO die-off happens as a direct result of microbe cell death. For example, the excess gases released from ruptured microbe cells can cause symptoms that mimic the different types of SIBO.
If someone has a leaky gut, the toxic waste products may also cause uncomfortable digestive symptoms. Intestinal permeability can allow these toxins to leak out of the GI tract, yielding signs of die-off.
A ruptured microbe’s nutrients also help to explain die-off symptoms. Other bacteria, archaea, and microbes living nearby feast on these nutrients, producing more gas as a byproduct and exacerbating digestive discomfort.
What Are the SIBO Die-Off Symptoms?
The SIBO die-off symptoms are worsening SIBO and flu-like symptoms. Flu-like symptoms include but are not limited to:
- Chills
- Fatigue
- Muscle aches
- Brain fog
- Headaches
- Fever
Worsening SIBO symptoms most likely occur due to the excess gases released by and as a byproduct of dying small intestinal microbes. Many of these gasses are the same ones linked to bacterial overgrowth symptoms.
The flu-like symptoms more likely happen due to toxins leaking out of the GI tract. In the presence of toxins, the body mounts an immune response. More specifically, immune system cells called cytokines cause these symptoms.
Cytokines are responsible for promoting the growth and activity of other cells of the immune system. Two well-known classes of cytokines are interleukins and interferons. Interleukins upregulate white blood cells; interferons help activate T-cells and other essential players in the immune response.
In addition to these more general die-off symptoms, the different types of SIBO can come with their own unique signs that improvement is taking place. Learn about the die-off symptoms by SIBO type next.
Methane SIBO Die-Off Symptoms
Methane SIBO is also known as intestinal methanogen overgrowth (IMO) because it happens when methane-producing archaea, not bacteria, multiply. It can be diagnosed with a breath test detecting levels of exhaled methane gas (CH4).
This SIBO type features symptoms like constipation and, less commonly, diarrhea. It is also associated with weight gain and high body fat. IMO commonly co-occurs with constipation-dominant irritable bowel syndrome (IBS-C).
Antibiotics do not always work for IMO since methanogens, not bacteria, cause it. However, studies have found that a combination of antibiotics may work better than rifaximin alone. One case report also found that a homemade Elemental Diet improved methane SIBO symptoms.
When people start implementing improvement strategies, people may experience symptoms of methanogen die-off. Constipation may worsen before getting better. People may also experience other common methane SIBO die-off signs like:
- Fatigue
- Brain fog
- Headaches
Why These Symptoms Occur
These symptoms may result from methane gas and toxin release after methanogen cell walls rupture. However, they may also come about due to the loss of methanogens.
In optimal numbers, these archaea promote digestion. Methanogens promote digestion by consuming hydrogen gas (H2), a byproduct of broken-down carbohydrates. A deficiency of methanogens, such as what might occur when addressing IMO, may cause excess hydrogen gas in the gut.
Excess hydrogen gas is linked to the symptoms of another SIBO type: hydrogen SIBO. Until this gas subsides, people may experience hydrogen-SIBO-like symptoms, especially diarrhea.
Hydrogen SIBO Die-Off Symptoms
Hydrogen SIBO happens as a result of an overgrowth of hydrogen-producing bacteria in the small intestine. These bacteria typically live in the large intestine. The most common species of hydrogen-producing bacteria in the colon are Bacteroides, Ruminococcus, and Roseburia.
These bacteria may migrate to the small intestine for various reasons and multiply. The most likely reason they overgrow is due to an excess amount of undigested carbohydrates, hydrogen-producing bacteria’s fuel of choice.
When these bacteria feast on carbs, they release H2 as a byproduct. A common sign of excess H2 in the gut is diarrhea. Hydrogen SIBO and a related condition, diarrhea-dominant IBS (IBS-D), feature diarrhea as a primary symptom.
Antibiotics, antimicrobials, and certain diets may help alleviate diarrhea and other SIBO-related digestive complaints. These methods aim to kill off hydrogen-producing bacteria in the small intestines, among other goals. The immediate result is die-off symptoms, such as:
- Increased diarrhea
- Flu-like symptoms
- Worsening or new mental and physical health symptoms
Why These Symptoms Occur
The first two symptoms can be explained by hydrogen-producing bacteria death. Recall that the toxins, gases, and nutrients released during the cell death process can bring about these symptoms.
Mental and physical health may suffer as a result of hydrogen SIBO die-off. Excess hydrogen produced in the gut is absorbed into the bloodstream and delivered to the rest of the body and the brain.
Lower levels of hydrogen-producing bacteria when addressing SIBO are associated with conditions like Parkinson’s, rheumatism, cardiovascular disease, and Crohn’s. H2 also protects the brain from oxidative stress; without this gas, mental illnesses like depression may worsen.
Hydrogen Sulfide SIBO Die-Off Symptoms
Hydrogen Sulfide SIBO features an excess of sulfate-reducing bacteria that produce hydrogen sulfide gas (H2S). H2S is typically a trace gas in the gut. It is produced from the digestion of proteins that contain the amino acids cysteine, methionine, and taurine.
Sulfate-reducing bacteria typically live in the colon (the large intestine). If they migrate back to the small intestine, they may feast on undigested proteins and produce an excess of H2S.
In high concentrations, H2S gas is toxic. Its accumulation in the digestive tract is associated with diarrhea and diarrhea-dominant IBS (IBS-D). Sulfurous-smelling gas may also indicate this SIBO type.
A low-sulfur diet, antibiotics, and/or antimicrobials are the best methods for sulfate-reducing bacterial overgrowth. As with other types, treatment for hydrogen sulfide SIBO can cause die-off symptoms, such as:
- Worsening diarrhea and sulfurous-smelling gas
- Increased risk of certain digestive conditions
- Neurotoxicity
Why These Symptoms Occur
These symptoms are primarily a result of the release and accumulation of excess hydrogen sulfide gas. Remember that addressing hydrogen sulfide SIBO requires killing off sulfate-reducing bacteria, which will cause a temporary increase in diarrhea, gas, and other SIBO symptoms.
There is a risk of exacerbating other conditions sensitive to H2S gas. Colorectal cancer, ulcerative colitis, and IBS-D are linked to increased levels of hydrogen sulfide gas.
Additionally, recall that we mentioned H2S is a neurotoxin in large amounts. It can negatively impact the brain, as well as respiration and the cardiovascular system. As such, people may temporarily experience symptoms like sensitivity to light or sound, headaches, dizziness, and more.
When Does SIBO Die-Off Occur?
SIBO die-off occurs when someone begins a regimen to kill off overgrown bacteria in the small intestine. Symptoms may begin a few hours after the regimen at the earliest or up to a week at the latest.
These symptoms are a sign that improvement is well on its way. Symptoms occur during a course of antibiotics, but herbal antimicrobials and some diets aiming to destroy overgrown bacteria can also cause die-off symptoms.
Symptoms that emerge after completing around a week of ceasing the use of antibiotics or antimicrobials are probably not signs of die-off. They may be symptoms of an infection or virus, so make sure to see a doctor.
How Long Do SIBO Die-Off Symptoms Last?
SIBO die-off symptoms may last for as little as a few days or for the duration of when someone is addressing SIBO. They are temporary and should dissipate as the overgrown gut bacteria die and are cleared out of the digestive tract.
Die-off symptoms should never continue after the time spent addressing SIBO. If bacteria are not being killed off, die-off symptoms should not occur. Die-off symptoms that emerge after that time could indicate a new overgrowth.
Experts estimate that SIBO re-occurs in 45% of people who address SIBO, especially when using antibiotics. Recurrence rates are also higher in older adults, people who use proton pump inhibitors (PPIs), and post-appendectomy patients. Early recurrence occurring within three months is most common, but it is also possible to develop a new cause of SIBO later than that.
SIBO Die-Off Experience
People may have heard horror stories about SIBO die-off that may or may not be true. Regardless, fear of SIBO die-off symptoms is not a reason to avoid treatment. The symptoms are temporary, and the benefits of undergoing them far outweigh the disadvantages.
Without getting treatment, people can experience worsening symptoms. Complications are also possible and may include incomplete digestion, intestinal permeability, weight changes, malnourishment, vitamin deficiencies, damage to the central nervous system, osteoporosis, and kidney stones.
Understanding what to expect from the SIBO die-off process can alleviate people’s anxiety. Here are some frequently asked questions about SIBO die-off to help individuals set their expectations ahead of time.
How Do SIBO Die-Off Symptoms Start?
SIBO die-off symptoms can start as soon as treatment begins or up to a week after someone has started a treatment regimen. Remember that die-off is symptomatic of antibiotics and antimicrobials working. It will not begin until the treatment starts to kill off the bacterial overgrowth.
Importantly, some people do not experience die-off symptoms. They may have a milder overgrowth, reducing the amount of gas released and nutrients available for other bacteria to feast on. Or they may lack a strong immune response to the toxins released when overgrown bacteria die.
Other people experience symptoms unrelated to SIBO die-off. For example, someone might be allergic to the antibiotic they are taking to eliminate the overgrowth. Allergic reactions to rifaximin antibiotics are uncommon but include rash, hives, itching, peeling skin, wheezing, tightness in the chest, trouble breathing, and swelling in the face.
What Influences How Long SIBO Die-Off Lasts?
The severity of the overgrowth, immune system activity, and the efficiency of the body’s natural detoxification pathways are factors that influence how long SIBO die-off lasts. Many people experience the symptoms for only a few days; others may experience die-off for a week or longer.
How severe someone’s digestive symptoms will be depends on the level of overgrowth, in particular. The more bacteria that die off when addressing SIBO, the more severe someone’s die-off symptoms tend to be. The reverse is also true: the milder the overgrowth, the milder the die-off symptoms.
Flu-like symptom severity mostly depends on the immune system and detoxification pathways. A highly active immune system will produce a more robust immune response to toxins and make someone feel sicker. Meanwhile, the more efficient someone’s identification pathways are, the faster their body will eliminate toxins.
Can SIBO Symptoms Get Worse During Die-Off?
Yes, SIBO symptoms can get worse during die-off, but they may also get progressively better when addressing SIBO. Whether someone experiences symptoms depends on the factors listed above (severity of the overgrowth, immune system response, and detoxification pathway efficiency).
Think of SIBO die-off symptoms in the same way as a skin purge. When introducing a new skincare product, things may get worse before they get better. Quitting the use of the product may alleviate those negative skin symptoms, but the user won’t get the benefits the product also offers.
When SIBO is initially addressed, it may cause an initial worsening of diarrhea, constipation, bloating, gas, or stomach pain. However, without pushing through these symptoms, individuals must continue to deal with chronic SIBO symptoms and, eventually, the complications that may result.
What Are the Symptoms of Bacteria Die-Off?
The symptoms of bacteria die-off are a worsening of SIBO-like digestive problems and flu-like symptoms. Someone’s digestive problems typically mimic the type of SIBO they have. For example, someone with methane SIBO may experience severe constipation during die-off.
Flu-like symptoms are a sign the immune system is eliminating toxins and clearing away waste products from the digestive tract. Common flu-like symptoms people with SIBO experience are fatigue, body aches and pains, headaches, and congestion.
Bacteria die-off can also worsen SIBO stool and gas. Learn more about why that is the case below.
SIBO Die-Off Stools
SIBO causes bacterial deconjugation of bile acids. Bile acids play a crucial role in absorbing fats, and they can’t perform this function when deconjugated from bacteria. Something similar happens when SIBO treatments destroy bacteria- the leftover bile acids alter fat absorption in the gut.
Poor fat absorption means much of the fats consumed through diet end up passing through the gastrointestinal tract undigested. They can cause SIBO stool, which is recognizable by its abnormally pale color, bulky appearance, and particularly foul smell.
Someone may experience new or worsening SIBO stool during die-off. The excess fat may cause or worsen diarrhea or constipation, especially in people who normally experience these SIBO symptoms.
SIBO Die-Off Gas
Gas is common in people with SIBO. Most of this gas is released as flatulence, but some of it passes into the bloodstream and is released through the breath. Gas is also a byproduct of bacteria and methanogens dying.
The chemical reactions needed to convert food into hydrogen and other gases occur inside the cell wall. When this cell wall ruptures, these gases spill out into the gut. Some of that gas is released when someone exhales; most of it leaves the body as flatulence.
During SIBO die-off, someone may experience an uptick in gas. People with hydrogen sulfide SIBO, in particular, may have gas that smells unpleasant or like rotten eggs, which is characteristic of hydrogen sulfide gas.
When SIBO Die-Off Symptoms Aren’t Normal
SIBO die-off symptoms that last a long time, especially after ceasing treatment, are a sign of concern. Die-off should never last longer than a few weeks. Most people experience the symptoms for no longer than 10 to 14 days since this is the typical length of a course of antibiotics or antimicrobials.
Other times, people believe they are dealing with die-off symptoms when they are really having an allergic reaction to antibiotics or experiencing side effects of an herbal antimicrobial. It is also possible to have completely unrelated symptoms that come about due to an infection, virus, or other illness.
Anyone who experiences lasting die-off symptoms or symptoms that are severe enough to interrupt their daily lives should consult with a healthcare professional. SIBO die-off can be uncomfortable, but if they come with either of these two features, these symptoms may indicate another regimen to address SIBO would be better.
Your Journey to SIBO Recovery Has Begun
SIBO die-off symptoms indicate someone has begun the journey to better gut health. They may emerge a few days or up to a week after starting a new SIBO regimen and will go away with the continued regimen.
If you need support addressing SIBO or understanding more about bacterial overgrowth die-off, Revolution Gut Health is here for you. Our experts are ready to assist every step of the way.
Schedule a consultation with a Revolution Gut Health doctor to start your journey to SIBO recovery.