Contact and Enquiry

Small Intestinal Bacterial Overgrowth SIBO

Comprehensive care for digestive disorders by Dr. Akeel Alisa

What is SIBO?

Small Intestinal Bacterial Overgrowth (SIBO) is a condition where abnormally high numbers of bacteria accumulate in the small intestine. Normally, the small intestine contains relatively few bacteria compared to the large intestine. In SIBO, these bacteria interfere with digestion and nutrient absorption, leading to a wide range of uncomfortable symptoms.

SIBO is increasingly recognised as a hidden cause of persistent digestive problems. Many patients with symptoms previously thought to be “just IBS” are now found to have SIBO when properly tested.

Make an Enquiry

Common Symptoms of SIBO

SIBO can present differently from person to person, but typical symptoms include:

  • Abdominal bloating and visible distension
  • Excessive gas and belching
  • Abdominal pain or discomfort
  • Chronic diarrhoea, constipation, or alternating bowel habits
  • Nausea after eating
  • Fatigue and low energy
  • Unexplained weight loss or malnutrition
  • Vitamin deficiencies (especially B12, fat-soluble vitamins)

Because these symptoms overlap with other digestive conditions such as IBS or coeliac disease, professional assessment is crucial for an accurate diagnosis.

Causes and Risk Factors

Several factors can disrupt the balance of bacteria in the gut and contribute to SIBO:

  • Abnormal gut motility – when food and bacteria are not efficiently moved through the intestine.
  • Structural problems – scar tissue, diverticula, or previous surgery affecting the gut.
  • Underlying conditions – such as diabetes, scleroderma, or Crohn’s disease.
  • Low stomach acid – reduces the natural defence against bacterial overgrowth.
  • Long-term medication use – particularly proton pump inhibitors (PPIs) or antibiotics.
  • Previous gastrointestinal infection – “post-infectious” IBS may sometimes be due to SIBO.

When to See a Gastroenterologist

You should seek professional help if you experience:

  • Persistent bloating and discomfort that does not improve with diet changes
  • Chronic diarrhoea or constipation without a clear cause
  • Weight loss or nutritional deficiencies
  • Symptoms of IBS that fail to respond to standard treatments

A gastroenterologist can determine whether your symptoms are due to SIBO, IBS, coeliac disease, or another digestive disorder.

Diagnosis of SIBO

The most reliable non-invasive method to diagnose SIBO is a hydrogen/methane breath test. After drinking a sugar solution (usually lactulose or glucose), breath samples are taken over time to measure gas levels produced by bacteria in the small intestine.

Other investigations may include:

  • Blood tests to check for nutritional deficiencies
  • Stool tests to rule out infections or inflammation
  • Imaging or endoscopy if structural issues are suspected

Accurate diagnosis ensures that the correct treatment plan is put in place.

Treatment Options for SIBO

1. Antibiotic Therapy

Specialist antibiotics, such as rifaximin, can reduce bacterial overgrowth in the small intestine. In some cases, combination therapy is used if methane-producing bacteria are identified.

2. Dietary Management

  • A low FODMAP diet may help reduce symptoms.
  • Some patients benefit from a specific carbohydrate diet (SCD) or low-fermentation diet.
  • Dietary adjustments should always be supervised by a gastroenterologist or dietitian to avoid nutritional deficiencies.

3. Probiotics and Gut Health Support

Certain probiotics may help rebalance the gut microbiome, though evidence varies and should be tailored to each patient.

4. Addressing Underlying Causes

If SIBO is linked to reduced motility, diabetes, or structural changes in the intestine, treating the root cause is essential to prevent recurrence.

Living with SIBO

SIBO can be a recurrent condition, but with accurate diagnosis and ongoing specialist support, most patients experience significant improvement in symptoms and quality of life. Regular monitoring, nutritional support, and personalised treatment plans help reduce relapses.

Why Choose Specialist Care for SIBO?

SIBO is often misdiagnosed as IBS or dismissed as a “functional” issue. Consulting a gastroenterologist offers several benefits:

  • Precise testing and diagnosis to confirm SIBO.
  • Tailored antibiotic and dietary treatments for effective symptom control.
  • Monitoring for nutritional deficiencies to prevent long-term complications.
  • Holistic care addressing gut health, diet, and underlying conditions.
5.0 Rating on Doctify

What Patients Say About Dr Alisa

Read testimonials from patients who have experienced Dr Alisa's expert care.

My consultation with Dr Akeel Alisa was highly satisfactory and he was very thorough. The Gastroscopy procedure was performed satisfactorily with no pain or discomfort at all. I am very pleased with treatment received so far.

Verified Patient

I was fully vaccinated investigated by Dr Akeel Alisa and I was reassured. My endoscopy and colonoscopy were straight forward and painless. I am very happy with the care I received.

Verified Patient

Dr Akeel Alisa and Nursing team at Cromwell Hospital Endoscopy team offered me great care and all was perfect. Well pleased.

Verified Patient