Helicobacter pylori (H. pylori) is a common type of bacteria that lives in the acidic environments of your stomach and upper small intestine. An H. pylori breath test, also called a urea breath test, can help a doctor diagnose infections caused by this type of bacteria.

More than half the world’s population is thought to be living with H. pylori. Most people do not have any symptoms.

But when an infection grows too much, it can lead to stomach ulcers and chronic stomach inflammation. It may even increase your risk of developing stomach cancer.

The H. pylori breath test is the most popular noninvasive test for diagnosing H. pylori. Read on to learn more about how this test works, what to expect, and how much it costs.

H. pylori is a common type of bacteria that lives in the stomach and upper small intestines of about 35 percent of people living in the United States. Infections often start in childhood and can persist throughout life if left untreated.

Most people never have any symptoms. But having H. pylori increases your risk of developing:

An H. pylori breath test can help a doctor diagnose the cause of these conditions and may be performed if:

  • you have an ulcer in your stomach or upper small intestine
  • you had an ulcer in the past and were never tested
  • you were already diagnosed with H. pylori and are being retested to see if treatment was effective

A doctor may give you specific instructions on how to prepare for your test. The specific instructions you receive may vary slightly, but you’ll likely be told to:

Your test should be quick and painless. It’s usually performed at a laboratory, but home kits are also available.

Your test will take about 40 minutes. Here’s how the procedure usually goes:

  1. You’ll exhale into a balloon-like bag. The amount of carbon dioxide in your breath is measured.
  2. You’ll drink a small amount (or consume a capsule) of a lemon-flavored solution that contains urea.
  3. About 15 minutes later, you’ll breathe into the bag again. The amount of carbon dioxide is then measured a second time.
  4. You’ll be free to go home after the second measurement of carbon dioxide.

H. pylori bacteria breaks down urea in your stomach and releases extra carbon dioxide in your breath. This test can detect an H. pylori infection by looking at the difference in carbon dioxide levels in your first and second breath samples.

Here’s what your results mean:

  • Positive. You will test positive for H. pylori if the amount of carbon dioxide is higher in your second sample than in your first. This means that you have the bacteria in your stomach.
  • Negative. You will test negative for H. pylori if there’s no difference between samples. This means that you do not have the bacteria in your stomach.

The doctor will contact you when your results are available. They’re usually available within a couple of days of the testing procedure.

If you test negative, the doctor may want to order other tests to understand what’s causing your symptoms.

Other tests are available to help doctors diagnose H. pylori. These tests can be used alongside a breath test. Examples include:

  • Endoscopy. An endoscopy involves putting a long tube with a camera down your throat and into your stomach. A doctor can look for signs of inflammation and irritation in your stomach. They can also take a small tissue sample to test for bacteria.
  • Blood tests. Blood tests look for antibodies that indicate your immune system has fought H. pylori bacteria. They cannot tell you whether you’re currently infected or were infected in the past.
  • Stool tests. Stool tests look for signs of the bacteria in your stool.

Prices for H. pylori breath tests vary based on the laboratory you visit or the manufacturer of your home test. Your insurance may cover part or all of the cost of your test if it’s deemed medically necessary.

Lab prices can range from around $150 to $450. Home tests may be slightly cheaper.

Stool tests are typically cheaper than breath tests but are slightly less accurate. Blood tests also tend to be cheaper, but they are even less accurate.

You may not need treatment if you do not have any problems associated with H. pylori and are not at an elevated risk of stomach cancer.

H. pylori is usually treated with two different antibiotics. This helps prevent bacteria from developing resistance to one of the antibiotics.

Your doctor may also prescribe or recommend an acid-suppressing drug to help give your stomach lining time to heal. These drugs may include:

Due to increases in antibiotic resistance, researchers are also examining the potential benefits of prescribing three antibiotics, taken one after the other.

An H. pylori breath test looks for evidence of an overgrowth of H. pylori bacteria in your stomach and upper small intestines. The test involves blowing into a balloon-like bag to measure carbon dioxide levels in your breath.

If you test positive for H. pylori, your doctor can help you decide on the next steps. Treatment usually includes taking multiple antibiotics and medications that lower acidity levels in your stomach.