Find answers to what is causing your Digestive Symptoms

FxMed is proud to exclusively partner with Auckland Gut Clinic

Auckland Gut Clinic offer specialist breath testing services in NZ and the only lab to offer the convenience of an at home test kit.

What is SIBO?

Normally, bacteria are found in the trillions in the large intestine, where they perform various functions for the human body.

SIBO is defined as an increase in the number of bacteria, and/or changes in the types of bacteria present in the small intestine.

  • In most patients, SIBO is not caused by a single type of bacteria, but an overgrowth of the bacteria that should normally be found in the colon.

SIBO breath test

Breath testing is also available through us to make it easier for you to access. It is a simple, non-invasive test that is used to diagnose SIBO. Knowing the type and level of gases produced aids targeted treatment and forms a base line for follow up comparison.

Common Symptoms of SIBO

  • Postprandial bloating/abdominal distension with associated discomfort
  • Gas and belching
  • Food Intolerances
  • Constipation (generally associated with methanogenic bacteria)
  • Diarrhoea (generally associated with hydrogenic bacteria)
  • Immune activation (e.g. food sensitivities)
  • Nutrient deficiencies i.e. vitamin B12 & Iron
  • Weight loss / weight gain
  • Fatigue or brain fog
  • Fibromyalgia


  • Prevalence estimates are based on a percentage of the population with Irritable Bowel Syndrome (IBS). This is 11-14% of the population globally and 17% in New Zealand.
  • It is the most common gastrointestinal diagnosis in primary care although it is thought that up to 50% of people with symptoms of IBS do not consult their GP..
  • Studies also show that over 50% of patients diagnosed with IBS actually have SIBO.

How does the SIBO Breath Test work?

  • A restricted diet is required for 24 hours in preparation.
  • Following a collection of a baseline breath sample, either a lactulose (or glucose) test substrate is consumed.
  • The bacteria may ferment the lingering substrate and produce hydrogen and/or methane. These gases are absorbed into the bloodstream and exhaled through the breath. Breath samples are collected every 15-20 minutes (depending on the substrate used) for up to 3 hours and analysed for the amount of Hydrogen, Methane and CO2 produced.
  • This test can be done at home and samples sent to Auckland Gut Clinic for analysis.

Click on individual test for more detail:

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