How to Diagnose and Overcome Small Intestinal Bacterial Overgrowth

This post is the third in a series about Small Intestinal Bacterial Overgrowth (SIBO). If you haven’t read the previous posts, start here or read post two. This post dives into the diagnosis and treatment of SIBO.

Review: What Is SIBO?

SIBO occurs when there is an abnormal increase in the population of bacteria in the small intestine. This overgrowth can lead to digestive symptoms such as bloating, diarrhea, constipation, gas, and abdominal discomfort.

How to Test for SIBO: The Gold-Standard Approach

The most reliable way to diagnose SIBO is through a breath test. This test measures the gases produced by bacteria in the small intestine, specifically hydrogen, methane, and hydrogen sulfide. A gastroenterologist can administer this test in-office, or you can order a convenient home test kit. Many patients find the home test more comfortable and convenient.

Prepping for the SIBO Breath Test

Before the test, you’ll follow a special prep diet for one day. This diet restricts fiber-rich foods that fuel bacteria in the small intestine. This means for one day, you are limited to these foods:

• Proteins like meat, fish, and eggs
• Healthy fats
• Broth
• Simple carbs such as white bread and white rice

Performing the SIBO Breath Test

On test day, you’ll provide a baseline breath sample and then consume a lactulose (or glucose) solution. After that, you’ll give breath samples every 15-20 minutes for 2-3 hours. The levels of gases detected in your breath help identify the presence of bacterial overgrowth in your small intestine. They also help determine the type and location of the overgrowth.

Interpreting SIBO Test Results

A positive SIBO test indicates an overgrowth of bacteria that produce either:

• Hydrogen gas (associated with diarrhea)
• Methane gas (typically linked to constipation, caused by archaea)
• Hydrogen sulfide (often causing foul-smelling gas).

Knowing which type of gas is present is essential for developing an effective treatment plan.

SIBO Treatment: Tailored Approaches for Long-lasting Results

Treatment for SIBO is personalized and multi-faceted. Here’s an overview of common strategies used by functional medicine practitioners, including myself.

Step 1: Reduce Bacterial Overgrowth

Pharmaceutical or herbal antimicrobials can “knock down” bacterial populations.

• Antibiotics: The gold-standard antibiotic for SIBO is Xifaxan (Rifaximin), particularly for hydrogen-dominant cases. If methane-producing archaea are present, Neomycin may be added. While antibiotics are often prescribed for 10 days, research shows 30 days can be more effective.
• Herbal Antimicrobials: Herbal therapies may be better tolerated by some. These plant-based treatments offer broad-spectrum antimicrobial action without the side effects of antibiotics. Herbal protocols are tailored to the type of bacteria, gas level, and the patient’s constitution.

Step 2: Break Down Biofilms

Bacteria and yeast create biofilms – sticky, protective layers that shield them from antimicrobial treatments. Taking biofilm-busting enzymes or supplements like NAC (N-acetylcysteine) helps disrupt these barriers, allowing treatments to work more effectively.

Step 3: Starve Bacteria with Diet

Some practitioners recommend a low-FODMAP, elemental, or low-fermentation diet to reduce bacterial load. This can help patients be more comfortable during treatment; however, following these restricted diets is best done for a limited time.

Should You Take Probiotics During SIBO Treatment?

The use of probiotics during SIBO treatment is controversial. While there’s no conclusive research proving their benefit during active treatment, many cases of SIBO involve imbalances in the colon (dysbiosis). Carefully selected probiotics can improve the colon microbiome.

• SIBO sufferers often tolerate probiotic strains like soil-based organisms, Bifidobacterium, or Lactobacillus plantarum.
• Avoid overloading with random probiotics, especially those containing Lactobacillus strains that produce histamine, which can exacerbate symptoms in SIBO patients.

Preventing SIBO Relapse: Fixing the Root Cause

People commonly relapse after SIBO treatment unless they address the root cause. Functional medicine focuses on identifying and correcting underlying issues, such as:

• Gut motility problems
• Nutrient deficiencies
• Imbalances in gut microbiota

We discuss how to prevent relapse in the next post.

Key Takeaways:

• The breath test is the gold standard for diagnosing SIBO.
• Your practitioner should personalize your treatment, and include options like antibiotics or herbal antimicrobials, biofilm disruptors, and diet adjustments.
• Addressing root causes is crucial to preventing relapse.

Take Control of Your Gut Health: Order Your SIBO Breath Test Today

If you suspect you have SIBO, getting tested is the first step toward finding relief. You can easily order an at-home SIBO breath test, which conveniently allows for accurate diagnosis from the comfort of your home. Once you have your results, we can work together on a personalized treatment plan to restore your gut health and prevent future relapses.

Ready to take control of your digestive health? Order your SIBO breath test and get started!

In the next post, I’ll dive deeper into strategies to prevent SIBO relapse. I will also discuss how to maintain gut health for the long term.

I welcome any questions or comments about this topic below.