Urea Breath Test


The urea breath test is a rapid diagnostic procedure used to identify infections by Helicobacter pylori (H. pylori), a spiral bacterium implicated in gastritis, gastric ulcer, and peptic ulcer disease.

How does it Work?
It is based upon the ability of H. pylori to convert urea to ammonia and carbon dioxide. Urea breath tests are recommended in leading society guidelines as a preferred, non-invasive choice for detecting H. pylori after treatment.

Patients swallow urea labeled with an uncommon isotope. In the subsequent 10–30 minutes, the detection of isotope-labeled carbon dioxide in exhaled breath indicates that the urea was split. This indicates that urease (the enzyme that H. pylori uses to metabolize urea) is present in the stomach, and hence that H. pylori bacteria are present.

I have finished my antibiotics, why do I need to wait 4 weeks for the breath test?
The test measures active H. pylori infection. If antibiotics are depressing the amount of H. pylori present, or the stomach conditions are less acidic than normal, the amount of urease present will be lessened. Accordingly, the test should only be performed 14 days after stopping acid reducing medication (proton pump inhibitors, PPI) or 28 days after stopping antibiotic treatment.