Would you know if your dog had small intestinal bacterial overgrowth … known as SIBO? Most dog owners have no idea their dog has SIBO. They notice the signs … but SIBO often goes undetected because vets don’t look for SIBO. So it’s time to learn more about this fast growing gut issue …
What Is SIBO?
Your dog’s gut bacteria are a vital part of his health and his immune system. They help your dog digest food, absorb vitamins and eliminate waste.
These bacteria are supposed to live in your dog’s large intestine and colon. The small intestine normally has low levels of bacteria. But sometimes other bacteria develop in the small intestine … when this happens, it’s called small intestinal bacterial overgrowth (SIBO). SIBO can interfere with your dog’s digestion and nutrient absorption. And that’s not the only problem.
Your dog’s gut has a protective mucous lining … but bacterial overgrowth can damage it. Then the damaged mucus allows biofilms to grow. Biofilms help unwanted bacteria hide from your dog’s immune system, which makes them harder to control.
The bacteria feed off undigested food in the small intestine. This causes fermentation that creates hydrogen. In turn, hydrogen feeds organisms called archaea that produce methane. As you can imagine, hydrogen and methane in your dog’s small intestine can make him gassy and bloated.
We don’t hear much about SIBO in dogs … but Roger M Batt BVSc PhD told a WSAVA meeting that it’s more common than vets think. This is likely because it’s hard to diagnose and the causes aren’t well understood. So it’s important to know how to recognize it in your dog.
Signs of SIBO In Dogs
Here are some symptoms that suggest your dog could have SIBO.
- Chronic or intermittent diarrhea
- Weight loss or inability to gain weight
- Stunted growth in a young dog
- Extreme hunger, eating stools
- Gassiness (flatulence)
- Abdominal pain
- Intermittent vomiting
- Malabsorption problems issues like EPI, IBS or IBD
- Acid reflux or GERD (gastroesophageal reflux disease)
- Food intolerances and sensitivities
- Skin issues
- Leaky gut
- Autoimmune disease
Another sign of SIBO is that your dog’s symptoms may get worse if you give him probiotics with Lactobacillus or Bifidobacterium strains. He might get extra gassy, or his constipation or diarrhea might worsen. (But don’t worry, there’s a solution for that … keep reading!)
What Breeds Get SIBO?
SIBO can happen to any dog … but German Shepherds may be more prone to it than others.
Studies on SIBO dogs show German Shepherds have lower levels of IgA (immunoglobulin A) than other breeds. IgA is an immune antibody that supports mucosal health in the gastrointestinal tract. However, there’s no conclusive evidence that this is what leads to more SIBO in the breed.
What Causes SIBO in Dogs?
Vets often don’t know the causes of SIBO in dogs. That leads some to suggest renaming it antibiotic-responsive diarrhea (ARD). But not all dogs with SIBO have diarrhea, so that doesn’t really make sense.
In conventional medicine, most SIBO is classed as “idiopathic” … the medical term for diseases of unknown origin. Idiopathic SIBO can appear in young dogs without any other digestive issues. It can start when they’re puppies. Diarrhea and gassiness are the most common signs of SIBO for these dogs. They may have little appetite … and might experience weight loss (or fail to gain weight).
Others speculate that SIBO is a secondary complication of other intestinal diseases. Dr Jorg M Steiner of Texas A&M University told the WSAVA,
“Small intestinal dysbiosis should not be considered a primary disorder. There are several protective mechanisms that prevent a patient from dysbiosis. […] Any disease process that affects … the protective mechanisms can ultimately lead to small intestinal dysbiosis.”
For example, dogs with malabsorption issues like EPI (exocrine pancreatic insufficiency) or IBD (inflammatory bowel disease) may be more prone to SIBO. Dogs with chronic digestive issues like IBS (irritable bowel syndrome) or acid reflux can also be at risk.
So, it can be complicated. But if your dog has any chronic issues, SIBO could go hand-in-hand with other problems. And in the long run, untreated SIBO could make your dog’s chronic problems worse.
RELATED: How to choose the RIGHT probiotic …
How To Confirm Your Dog Has SIBO
Most vets find it very hard to diagnose SIBO, if they think to look at all. Here are some ways vets try to confirm SIBO, although none of these methods is conclusive.
- Regular bloodwork (CBC and chemistry panel), fecal analysis to check for parasites, X-rays or ultrasound to rule out obstructions. They may check for EPI with a a serum TLI (trypsin-like immunoreactivity) test.
- B12 and folate tests may help sometimes. but many dogs with SIBO have normal tests.
- Leaky gut test doesn’t tell you what’s causing the leaky gut. But because many dogs with SIBO also have leaky gut, it may help confirm SIBO.
- Breath hydrogen test can be one of the most reliable measures of SIBO but most vets won’t have the equipment to do it.
- Duodenal juice test is done via endoscopy, under sedation. It’s the gold standard for diagnosing SIBO, but still, many SIBO dogs will test normal.
- Unconjugated Bile Acid (UBA) test is a complicated test that’s hard to get … but dogs with SIBO have higher UBA.
As you can tell, these tests can be difficult, expensive and inconclusive. So when they suspect SIBO, vets will often try antibiotics to see if they help. Using antibiotics to confirm a diagnosis is common. But giving antibiotics without knowing your dog really needs them is irresponsible. And in the case of SIBO, it will only make things worse …
Why Antibiotics Don’t Work For SIBO
So, after reading the paragraph above, you won’t be surprised to learn that the way many vets treat SIBO is with antibiotics. And they’re not even very effective. One problem is that antibiotics need to be given for a long time to get rid of SIBO. And even then, it often comes back.
The main antibiotic vets use for SIBO symptoms is oxytetracycline, which is often used for respiratory infections or tick-borne diseases. But oxytetracycline can damage the kidneys, affect bone and tooth development … and cause intestinal problems.
Your vet may also prescribe a drug like Metronidazole (flagyl) or Tylosin/Tylan. These are antibiotics that treat diarrhea. Vets often use them long-term for chronic diarrhea … or SIBO. Even with short term use, these drugs have known side effects … including, ironically, chronic diarrhea! But giving them long term is especially foolish. Here are a few reasons why.
- Don’t ever use antibiotics when you have other options. And with SIBO, you do (keep reading).
- Even after long term treatment, SIBO often reappears when you stop the drugs. So your dog could be on antibiotics for months or even years. Think about the long term damage to his gut!
- Treating GI problems with antibiotics is reckless. We all know that antibiotics cause gut issues. Antibiotics might eventually get rid of the bacteria overgrowth in your dog’s small intestine … but they’ll damage his overall gut health in the process.
- With antibiotic-resistant bacteria on the rise, antibiotics are risky … not just for your dog, but for all of us. Especially when there are safer solutions.
Make a rule that you’ll only use antibiotics when nothing else will do. Save antibiotics to save your dog’s life … not to manage chronic health issues. For SIBO there are better, safe options. So how can you recognize SIBO and treat it naturally and safely?
RELATED: Why you should avoid antibiotics for your dog …
SIBO And Gut Health
Holistic veterinarian Dr Odette Suter observes most dogs, cats and humans these days have some degree of SIBO. Like other gut health issues this starts with a poor microbiome transferred from mom. Then they get a poor diet and toxic environment, plus damage from deworming, antibiotics, vaccines and stress.
This creates an overgrowth of some bacteria, and “undergrowth” of others … usually combined with lack of microbe diversity. So Dr Suter views SIBO as part of a general microbial imbalance in the entire GI tract. The dog’s symptoms will usually allow her to diagnose the problem. However, she does do some microbiome testing for more specifics on how “off” the microbiome is … and that allows her to customize treatment.
Dr Dee Blanco takes a similar approach. She doesn’t view SIBO as a separate diagnosis in dogs like it is in humans. In part, shorter small intestines in dogs may be less prone to invasion by pathogenic bacteria. Dogs’ high hydrochloric acid may also help reduce SIBO risk.
To Dr Blanco, small intestinal bacteria are part of the overall gut health picture. They can lead to inflammation and leaky gut … but may not cause the “human” SIBO symptoms of GERD or burping. And Dr Blanco agrees diagnosis is difficult. She jokingly commented, “I haven’t been able to get one dog to blow ito the bag to test their methane levels. Try as I might!”
This broader approach makes sense to holistic veterinarians. They treat the “whole patient” … not just one “disease” or set of symptoms. And because they’re not using antibiotics, they don’t have to pin down a specific disease as the culprit. Holistic treatment options for SIBO are safe! So the good news is … if you suspect SIBO in your dog, you can do several things at home to manage it.
Home Remedies For SIBO In Dogs
The first step in managing SIBO In dogs is to support overall gut health. The foundation of a healthy gut is a good diet.
SIBO Diet For Dogs
The best diet to promote health in your dog is always a fresh, whole-food, raw-meat based diet. Here are some feeding guidelines for dogs with SIBO.
Avoid These Foods
- Grains, legumes, starchy vegetables – convert to sugar that feeds the bacterial overgrowth. Don’t give kibble to your SIBO dog!
- Fermented foods – can produce more gases in the digestive system.
- Fruit – provides sugars that feed the bacteria.
- Dairy – hard to digest for many dogs, especially with intestinal damage that reduces lactase production. Lactase is the enzyme that digests lactose in dairy foods.
Feed These Foods
- Lean proteins
- Leafy greens and other non-starchy vegetables
- Prebiotic foods to promote healthy bacteria – like mushrooms, fresh garlic, dandelion leaves
Next, add a probiotic supplement. Read this next section carefully … because you need to choose the right probiotic!
Probiotics For SIBO
There’s research showing that probiotics are more effective than antibiotics in controlling SIBO. One study in Argentina found treating with probiotics was better than Metronidazole, with no adverse effects. Another study started out with antibiotics but then gave one group probiotics for maintenance. After 6 months, 93% of the probiotic group remained SIBO-free (measured by hydrogen breath tests) … and all were free of abdominal pain. Other symptoms like flatulence, belching and diarrhea also improved in the probiotic group.
Read this next part carefully. It’s the most important thing you need to know about SIBO …
The most important factor in managing SIBO is choosing the right probiotic. With SIBO, you can’t just use whatever probiotic you happen to have in your cabinet. The wrong probiotics will make SIBO worse.
As mentioned earlier, probiotics with Lactobacillus or Bifidobacterium strains will make SIBO worse. That’s because probiotics have to travel through the small intestine to get to the colon (where they belong). And on their way, most probiotics will feed the bacterial overgrowth in the small intestine. That helps SIBO multiply … and compounds the problem. So you might see an increase in your dog’s digestive symptoms … like diarrhea, flatulence, constipation or acid reflux.
Instead, you need to use soil-based probiotics (SBOs) for your dog with SIBO. SBOs are spore-forming bacteria that have a protective outer layer that lets them move safely through the small intestine until they get to the colon. Once in the colon, they’ll get to work supporting beneficial bacteria throughout your dog’s GI tract. Don’t make the mistake of making SIBO worse with the wrong kind of probiotics!
RELATED: Which probiotic should you choose for your dog?
Digestive Enzymes For SIBO
Digestive enzymes can help your dog’s overall digestive symptoms. SIBO may be causing the problems … or they could stem from an associated chronic digestive problem like IBD or EPI. Holistic veterinarian Dr Jean Hofve suggests digestive enzymes can help break down the unwanted bacterial overgrowth. And they’ll improve your dog’s nutrient absorption.
When you’re dealing with SIBO, give your dog digestive enzymes ½-1 hour before food. Mix the powder into a slurry with water. Then you can syringe it into your dog’s mouth, 3 times a day.
The beauty of these home remedies for SIBO is that you don’t need to get your vet to run a bunch of expensive, even futile tests. You can give these remedies without a confirmed diagnosis. If your dog has SIBO symptoms … now you know how to get the bacteria under control.
RELATED: When to give your dog digestive enzymes …
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