The most common SIBO tests in the UK is a breath test. The SIBO breath test measures both hydrogen and methane gases in the breath with 24 hours diet prep needed (void of fermentable carbs) and a overnight fast. A fasting baseline level will be collected first, then carbohydrates such as lactulose and glucose are given as substrates. The lactulose or glucose samples are collected every 20 minutes for the next three hours. This SIBO breath test uk is also known as the glucose and lactulose breath test.

The Difference between lactulose and glucose SIBO Tests.

  1. Lactulose has the bigger advantage of detecting bacterial overgrowth throughout the small intestine, including the lower end where it most commonly occurs. Humans cannot digest or absorb lactulose, only bacteria can and because it is not absorbed, lactulose travels the entire length of the intestine, revealing SIBO at all portions of the intestine. Lactulose may be slightly less fermentable than glucose,3 but its ability to travel throughout the colon outweighs any difference in fermentation. A false positive result may occur if you have frequent diarrhea or know that you tend to experience a faster transit time. 
    On the other hand glucose is highly fermentable by bacteria, it is typically absorbed in the upper portion of the small intestines; thus, if SIBO exists in the lower portion of the small intestines, it may be missed which can show up as false negatives.

Does the NHS Test for SIBO?

SIBO Testing UK will or bacterial overgrowth testing will depend on the GP and the Gastroenterologist. In recent years, arranging a SIBO test in the UK through your GP is becoming more common, its still not widely used by many Gastroenterologists which is quite concerning. Gut health checks in general are unforunately very basic and often given false negatives. The other issues with going for SIBO treatment is that there are no standardized SIBO symptoms according to the NHS as they all fall under IBS, so you nearly have to plead with your GP to get one done, and then this could take months and months as it’s not seen as a priority. Also, even if the patient is given rifaximin or another antibiotic, they may not be looking at the root cause of why SIBO happened in the first place which may mean SIBO will keep on coming back if this is not addressed. At the clinic, we look at what caused SIBO and look at the wider eco-system which often reveals where the imbalances are and this often means looking at the large colon/bowel.

What About Hydrogen Sulfide SIBO?

If you do get a false negative there may be another reason for this. The other, less common or understood type of SIBO, hydrogen sulfide SIBO maybe present. There are currently no SIBO breath tests available for detecting hydrogen sulfide SIBO in the UK which makes diagnosis difficult. However, there is a way of interpreting the hydrogen breath test when you see a flat lining of methane and hydrogen on a lactulose breath test (below 3-4 for the duration of the test), especially when there smelly rotten-egg gas  present, should be treated accordingly.

Symptons of SIBO

  • Loss of appetite.
  • Abdominal pain.
  • Constipation
  • Mental Health Symptoms
  • Excessive Gas
  • Nausea.
  • Bloating.
  • An uncomfortable feeling of fullness after eating.
  • Diarrhea.
  • Unintentional weight loss.
  • Malnutrition

How to test for SIBO

While breath SIBO testing is by far the most commonly used in clinical practice, there are a number of other other indirect ways to screen for SIBO. Another common way we test in the clinic is through a gut bacteria test known as Comprehensive Digestive Stool Analysis (CDSA) test. There are a number of providers on the market but we tend to use such as Genova, GI Mapp or Doctors Data Labs. There are a number of markers to look for, including calprotectin, elastase and fat in the stool that indicate SIBO may be present. There are also some bacteria markers we look for that can indicate SIBO.  While a CDSA test is not a the most reliable way to definitively test for SIBO on its own, given that most clients are also testing a host of pathogens, gut function and levels of good bacteria, it is a sensible way to see what is happening in the wider eco-system to see why SIBO happened in the first place. Testing for SIBO can also be can be done in the comfort of your own home so you dont need to come into the clinic.

How we can help

Functional medicine takes a comprehensive approach to healthcare by examining not just the symptoms, but also the overall health and medical history of the patient to uncover potential underlying causes and especially with a condition such as SIBO. As IBS specialists, we focus on comprehensive gut health checks including the SIBO breath testing and microbiome testing to uncover what is causing the imbalance. We also look do tests for food intolerances and food allergy tests. We find that SIBO herbal treatment cheaper and more effective than antibiotics for SIBO and its alot safer for the beneficial flora. Although the stool test for IBS doesn’t show if you have SIBO its indicative of an issue which can contribute to SIBO which needs further investigation.