H. Pylori (Helicobacter Pylori) Breath Test / Urea Breath Test


What is the H. pylori breath test?

The H. pylori breath test is a simple and safe test. The test is used to:

  • Detect H. pylori bacteria.
  • Diagnose an active H. pylori infection.
  • Determine if treatment has cured the infection.

This test is also called the urea breath test.

What is H. pylori?

H. pylori (Helicobacter pylori) is a bacteria that infects your stomach or duodenum (first part of the small intestine). H. pylori bacteria can increase your risk of developing:

H. pylori is a major cause of peptic ulcer. The bacteria decreases the stomach’s protective mucus. This makes it easier for the stomach to be damaged from digestive acids.

Who gets H. pylori infections?

H. pylori infections are very common. About 50% of the world’s population is infected. However, most people never have symptoms.

When should I get a H. pylori breath test?

See your healthcare provider if you have pain in your digestive tract or symptoms of a peptic ulcer including:

  • Gnawing or burning pain in your middle or upper stomach between meals or at night.
  • Pain that comes and goes if you eat something or take an antacid.
  • Bloating.
  • Heartburn.
  • Nausea or vomiting.
  • Weight loss.

Test Details

What happens during the H. pylori breath test?

During the H. pylori breath test, you will be asked to exhale into a balloon-like bag. The amount of carbon dioxide you exhale into this bag is measured to provide a baseline level for comparison.

Next, you will be asked to drink a small amount of a pleasant lemon-flavored solution. The solution contains a substance called urea. Fifteen minutes after drinking the solution, you will exhale into a second bag. The amount of carbon dioxide you exhale into the second bag is also measured.

H. pylori bacteria (if present) breaks down the urea in the solution you drank, releasing carbon dioxide in the breath you exhale. So if the amount of carbon dioxide in your second sample is higher than the amount in your first sample, you have a positive test for the presence of H. pylori.

What steps do I need to take before the procedure?

Be sure to tell your healthcare provider if you are allergic to any medicines or if you are phenylketonuric. Follow these instructions:


  • Four weeks before your test, do not take any antibiotics or Pepto-Bismol® (oral bismuth subsalicylate).
  • Two weeks before your test do not take any over-the-counter or prescription proton pump inhibitors, such as omeprazole (Prilosec®), lansoprazole (Prevacid®), pantoprazole (Protonix®), rabeprazole (AcipHex®) or esomeprazole (Nexium®), dexlansoprazole (Dexilant®).

Do not stop taking any other medicine without first talking with your healthcare provider.

Food and drinks:

  • One hour before the test, do not eat or drink anything (including water).

On the day of the procedure

A healthcare provider will explain the procedure in detail and answer any questions you might have. The procedure lasts about 20 to 30 minutes.

After the procedure

  • Your breath samples are sent to the laboratory where they are tested.
  • You may resume your normal activities.
  • No restrictions.

Results and Follow-Up

When should I expect the result from my H. pylori breath test? What do the test results mean?

Test Results

  • Your healthcare provider will contact you as soon as your laboratory test results are available.
  • You will be treated with antibiotics if your test result indicates you have an H. pylori infection.
  • One month after antibiotic treatment, your provider might order a repeat breath test to make sure the infection has been cured.
  • If you have a negative test result and continue to have symptoms, your provider may order other tests to determine their cause.

Last reviewed by a Cleveland Clinic medical professional on 11/20/2020.


  • National Institutes of Health. National Cancer Institute. Helicobacter pylori and Cancer. (https://www.cancer.gov/about-cancer/causes-prevention/risk/infectious-agents/h-pylori-fact-sheet) Accessed 11/20/2020.
  • Lab Tests Online. Helicobacter pylori (H. pylori) Testing. (https://labtestsonline.org/tests/helicobacter-pylori-h-pylori-testing) Accessed 11/20/2020.
  • Merck Manual Professional Version. Helicobacter pylori Infection. (http://www.merckmanuals.com/professional/gastrointestinal-disorders/gastritis-and-peptic-ulcer-disease/helicobacter-pylori-infection) Accessed 11/20/2020.
  • Duck WM, Sobel J, Pruckler JM, et al. Antimicrobial Resistance Incidence and Risk Factors among Helicobacter pylori–Infected Persons, United States. (https://wwwnc.cdc.gov/eid/article/10/6/03-0744_article#:~:text=The%20prevalence%20of%20Helicobacter%20pylori,during%20their%20lifetime%20(1%29.) Emerging Infectious Diseases. 2004;10(6):1088-1094. Accessed 11/20/2020.
  • Chey W, Leontiadis G, Howden C, et al. ACG Clinical Guideline: Treatment of Helicobacter pylori infection. (https://journals.lww.com/ajg/Fulltext/2017/02000/ACG_Clinical_Guideline__Treatment_of_Helicobacter.12.aspx) Am J Gastro 2017;2(112):212-239. Accessed 11/20/2020.

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