H2-breath test

A hydrogen (H2) breath test can detect foodborne intolerances against lactose (milk sugar), fructose (fruit sugar) and sorbitol (artificial sweetener) as well as small intestinal bacterial overgrowth.


The cause is a deficiency of the small intestinal lining to split these substances, which can not be digested in the small intestine and reach the colon, where they are decomposed by intestinal bacteria, producing hydrogen (H2).



The examination should be carried out in case of

  • Unclear abdominal pain
  • Unclear diarrhoea
  • Flatulences
  • Feeling of fullness

Examining procedure:

  • Please consider that you must not eat for 12 hours, and not chew gum or smoke for 10 hours before the breath test. (We will give you further information about how to prepare at the medical practice.)
  • You should schedule about 2 hours for the test. First, you will drink a defined quantity of testing substance at the medical practice. After that, you will have to breath into a small measuring device at regular intervals (every 30 minutes), which will measure the concentration of hydrogen in the air that you breathe out.
  • Symptoms such as flatulences, bloating, cramps, and diarrhoea are also important for the diagnosis.