Small Intestinal Bacterial Overgrowth (SIBO) Treatment

Treatment of Small Intestinal Bacterial Overgrowth (SIBO) plays a critical role in minimizing complications.

SIBO occurs when microorganisms, normally expected to reside in the large intestine, proliferate in the small intestine. This condition increases gas production, impairs the function of bile and digestive enzymes, and reduces fat and vitamin absorption.

What are the symptoms of SIBO?

SIBO is often confused with irritable bowel syndrome, so symptoms need to be carefully evaluated.

• Abdominal bloating, belching, and increased gas
• Chronic or fluctuating abdominal pain
• Diarrhea, fatty stools, or constipation
• Unexplained weight loss and nutrient deficiencies

The severity of symptoms varies depending on the type of bacteria and co-existing conditions.

What are the causes and risk factors of SIBO?

To summarize in one sentence: impaired gut motility and anatomical changes facilitate the colonization of bacteria in the small intestine.

• Diabetic neuropathy, hypothyroidism that slow down bowel movements
• Structural disorders such as gastrointestinal surgeries, diverticula, fistulas
• Proton pump inhibitors, opioids, and immunosuppressive drugs
• Chronic diseases such as celiac disease, Crohn’s disease, scleroderma

How is SIBO diagnosed?

The most common diagnostic method is the hydrogen-methane breath test. Aspiration culture is considered the gold standard in suspicious cases. Laboratory tests can reveal B12, iron, and folate deficiencies.

What are the SIBO treatment methods?

The main goal in SIBO treatment is to reduce bacterial load, alleviate symptoms, and prevent recurrence.

Antibiotic Treatment

Locally acting agents such as rifaximin or neomycin are given for 10–14 days.

Dietary Adjustment

The FODMAP diet (an elimination diet to identify specific food triggers in sensitive individuals) limits carbohydrates that bacteria can ferment.

Probiotic and Prebiotic Support

Increases beneficial bacterial diversity, providing competitive inhibition.

Treating the Underlying Condition

Bowel motility disorders or anatomical obstructions are corrected.

Probiotic Bowel Wash (PBW)

Probiotic bowel wash is the direct infusion of a high-concentration live probiotic suspension into the small intestinal segment via endoscopy or nasoduodenal catheter. The aim is to “dilute” pathogenic bacteria in situ and accelerate the colonization of beneficial species.

Application Duration: Approximately 20-30 minutes, usually performed under sedation.

Effect: Rapidly shifts microbiota balance to a positive direction; may reduce the risk of recurrence after antibiotics.

Safety: Sterile preparation before the procedure is essential; careful evaluation is required for immunocompromised patients.

What is the FODMAP diet?

The FODMAP diet aims to reduce symptoms of irritable bowel syndrome (IBS) and SIBO such as bloating, abdominal pain, and diarrhea by temporarily restricting foods rich in fermentable short-chain carbohydrates (Fermentable Oligo-, Di-, Mono-saccharides And Polyols), which increase gas production and fluid retention in the intestines. This group includes fructan-containing grains and vegetables like wheat, rye, onion, garlic; galactooligosaccharides in legumes; fructose-rich fruits like honey, apples, pears; lactose in dairy products; and polyols (sorbitol, mannitol) in chewing gum, avocado, mushrooms.

The diet is implemented in three phases:

1. Elimination: High-FODMAP foods are removed as much as possible for 4-6 weeks.
2. Reintroduction: FODMAP groups are reintroduced one by one in a controlled manner to see the amount the patient can tolerate.
3. Personalized Maintenance: Foods that do not cause symptoms are permanently included in the diet, thus maintaining relief and preventing unnecessary restrictions.

The process must be carried out under the supervision of a dietitian or gastroenterology specialist; as excessive restriction can lead to insufficient fiber and a reduction in microbiota diversity.

Nutrition and Lifestyle Recommendations

When managing SIBO, diet and stress control reinforce the success of the treatment.

• A gradual transition to the FODMAP diet should be made, followed by personalized food reintroduction.
• Daily water intake and regular sleep positively affect bowel motility.

Post-Treatment Follow-up

After symptoms improve, bowel motility regulating medications (e.g., low-dose erythromycin) and probiotic courses can help prevent recurrence. A control breath test is usually planned after the 3rd month.