Test / Diagnostic Procedure: Breath Testing

Breath testing is used to establish the presence of small intestinal bacterial overgrowth (SIBO), which occurs when bacteria that are normally present in the colon have moved to the small bowel. The test is simple and non-invasive.

To book offline, call our Digestive Health centre directly on: 020 3653 2009

Enquiries: bookings.digestivehealth@onewelbeck.com

What is SIBO?

Small intestinal bacterial overgrowth (SIBO) occurs when bacteria which are normally present in the colon have moved to the small bowel. This is where glucose is usually absorbed, but if bacteria have increased in that area they will break down the glucose drink we give you and produce hydrogen and methane.

Bacterial overgrowth usually occurs because of abnormal movement of the gut. It is most common in patients with illnesses which directly or indirectly affect the gut and less common in patients with no underlying illness or Irritable Bowel Syndrome.

What is breath testing?

Breath testing will establish how much hydrogen and/or methane is in your breath. If bacteria have moved to the small bowel, which is where glucose is absorbed, they will break down glucose and produce hydrogen and methane.

The test is simple and non-invasive but is time consuming so we recommend you bring something with you to read. You can access our Wi-Fi network in our waiting areas.

You will give a breath sample by holding your breath and breathing out into a mouth piece attached to a specialist device that measures the gases in your breath sample. You will be asked to provide one fasting sample then given a sugary drink. You will return to the waiting area and return to give additional samples every 15 minutes.

You can drink water during the test but must have nothing else to eat or drink until the test is complete. You should not smoke until after the test and not use alcohol hand gel as this affects the breath monitor.

What happens after the test?

You will be able to travel home and continue with your normal activities after the test. Please contact us, should you have any problems.

The result will be compiled into a report which will be sent to your referring doctor. A follow up consultation will be arranged and the test results and any appropriate treatment will be discussed with you.

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May 2024


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SIBO Breath Testing Specialists