Understanding the H. pylori Breath Test: Procedure, Results, and What to Expect

Learn how the H. pylori breath test works, its significance for stomach health, and what to expect before, during, and after the procedure.

By Sneha Tete, Integrated MA, Certified Relationship Coach

Created on Sep 25, 2025

Learn how the H. pylori breath test works, its significance for stomach health, and what to expect before, during, and after the procedure.

What It’s Like to Take the H. pylori Breath Test

Helicobacter pylori (H. pylori) is a common bacterium that thrives in the acidic environment of the human stomach and upper small intestine. The H. pylori breath test, also known as the urea breath test, is a noninvasive, highly accurate method that helps healthcare professionals diagnose infections caused by this microorganism.

An estimated over half the global population lives with H. pylori, but many never experience any symptoms. When infection proliferates, however, it can lead to issues like gastritis, stomach ulcers, and even an increased risk for certain types of stomach cancer.

This article explains the H. pylori breath test in detail, covering its purpose, procedure, preparation, interpretation of results, alternatives, costs, treatment approaches, and frequently asked questions.

What is an H. pylori Breath Test?

The H. pylori breath test is designed to detect active infection with H. pylori in the stomach. This bacterium often establishes lifelong colonization starting in childhood, especially in regions where sanitation may be limited. In the United States, it is estimated that about 35 percent of individuals are infected.

Most infected individuals do not exhibit symptoms.
Persistent infection can cause:

Gastritis — inflammation of the stomach lining
Peptic ulcers — open sores in the stomach or upper small intestine
Stomach cancer
MALT lymphoma — cancer of the stomach’s lymphatic tissue

The urea breath test is especially useful for:

Diagnosing the cause of gastrointestinal symptoms (such as ulcers)
Testing individuals with a history of ulcers who have not previously been screened
Assessing the success of H. pylori eradication after treatment

How Does the H. pylori Breath Test Work?

The breath test leverages the unique ability of H. pylori to produce urease, an enzyme that breaks down urea (a compound naturally found in the stomach) into ammonia and carbon dioxide (CO₂). The test works as follows:

You consume a solution or capsule containing harmless, specially labeled urea (often with a ¹³C or ¹⁴C carbon isotope).
If H. pylori is present, its urease breaks down this urea, releasing labeled CO₂.
This labeled CO₂ enters your bloodstream and is exhaled in your breath.
By comparing breath samples before and after urea ingestion, the presence of labeled CO₂ indicates an H. pylori infection.

The higher the levels of labeled CO₂ in your second breath sample, the greater the likelihood of infection.

H. pylori Breath Test Procedure

The urea breath test is quick, noninvasive, and painless. It is usually performed at a laboratory, diagnostic center, or doctor’s office. At-home test kits are also available but may have specific instructions for collection and shipping.

Preparation Prior to the Test

Do not eat or drink for at least 6 hours before the test.
Stop antibiotics at least 4 weeks before testing.
Discontinue certain stomach medications 2-4 weeks prior. Medications to stop include:

Proton pump inhibitors (PPIs)
Histamine (H2) blockers
Bismuth subsalicylate (found in Pepto-Bismol and similar products)

Avoid chewing gum or smoking on the day of the test, unless otherwise advised by your doctor.
Continue other medications unless directed otherwise by your healthcare provider.

Step-by-Step Test Process

You will exhale into a special balloon-like bag or collection device to obtain a baseline breath sample.
You will drink a small amount of a lemon- or orange-flavored solution—or swallow a capsule—containing the labeled urea.
After about 15 minutes, you will provide another breath sample for analysis.
You are generally free to leave after the second sample is taken; the entire process typically takes about 40 minutes.

How The Test Feels

The test is painless and noninvasive—no needles or anesthesia are required.
Most people tolerate the flavored urea solution well; side effects are rare.

Interpreting Your H. pylori Breath Test Results

Laboratories analyze your breath samples to measure labeled CO₂ levels. The comparison between pre- and post-urea ingestion samples determines whether infection is present.

Negative result: A minimal increase in labeled CO₂ means H. pylori was not detected.
Positive result: A significant increase in labeled CO₂ indicates an active H. pylori infection.

Sensitivity and specificity for this test are both high (often above 95%), meaning it is quite accurate. In rare cases, recent use of antibiotics or acid-suppressing drugs can cause false-negative results, highlighting the importance of proper test preparation.

Possible Reasons to Perform the Test

You have unexplained stomach pain or symptoms suggesting ulcers.
You had an ulcer but were never previously tested for H. pylori.
You have completed H. pylori treatment, and your healthcare provider wants to confirm eradication.

Other Methods for H. pylori Detection

Besides the urea breath test, clinicians have several alternative diagnostic options:

Test Type	Sample Required	Invasiveness	Notes
Stool antigen test	Stool sample	Noninvasive	Detects active infection
Blood (serology) test	Blood sample	Noninvasive	Cannot distinguish past from current infection
Endoscopy with biopsy	Tissue from stomach lining	Invasive	Allows direct observation and sample collection but usually reserved for complex cases

Cost of the H. pylori Breath Test

The cost of the H. pylori urea breath test can vary depending on geographic location, healthcare facility, and insurance coverage.

The test cost can range from $100 to $400 without insurance.
Health insurance or government healthcare plans may fully or partially cover the cost if the test is deemed medically necessary.
At-home breath test kits are also available online or by mail, potentially at a lower price but may not be accepted by all clinicians for diagnosis or follow-up.

Treating H. pylori Infections

If your results confirm an H. pylori infection, your doctor will discuss treatment options with you. Eradication therapy typically involves:

Two antibiotics — usually clarithromycin, amoxicillin, or metronidazole, to overcome antibiotic resistance
A proton pump inhibitor — reduces stomach acid to enhance antibiotic effectiveness
Bismuth subsalicylate (sometimes) — may be added in certain regimens.

Treatment is usually prescribed as a “triple” or “quadruple” therapy and lasts for 10–14 days. Follow-up breath or stool antigen testing is often recommended at least 4 weeks after treatment to ensure infection clearance.

Frequently Asked Questions

Who should get an H. pylori breath test?

The H. pylori breath test is indicated for individuals with symptoms of ulcers, persistent gastrointestinal discomfort, a history of gastric issues, or when follow-up after treatment is necessary.

Is the H. pylori breath test safe for everyone?

The test is safe for adults, children over the age of 3, and pregnant individuals. Always inform your provider about pregnancy or underlying illness beforehand to confirm suitability.

What should I do if my test result is positive?

Your healthcare provider will discuss appropriate antibiotic-based treatment options and may recommend follow-up testing to confirm eradication. Completing the full course of prescribed therapy as directed is essential.

Can recent medication use affect test accuracy?

Yes, recent use of antibiotics or certain stomach medications (such as PPIs, H2 blockers, or bismuth) can lead to a false-negative result. Discontinue these medications ahead of time as instructed by your doctor for accurate results.

Are there risks or side effects associated with the test?

The urea breath test is generally very safe. Mild side effects such as transient nausea or a slight aftertaste from the urea solution are uncommon but possible.

Is the breath test better than stool or blood tests?

The breath test and stool antigen tests are considered the gold standard for active infection detection. Blood antibody tests are less specific because they do not distinguish between current and past infections.

Summary

The H. pylori urea breath test is a rapid, accurate, and safe method for diagnosing H. pylori infections linked to a range of gastrointestinal issues. Following proper pre-test instructions increases the chance of an accurate diagnosis. Treatment options are readily available for those who test positive, and follow-up is important to ensure successful eradication. If you suspect you have symptoms related to H. pylori infection or need follow-up after treatment, discuss the breath test with your healthcare provider for targeted, effective care.

References

Author

Sneha TeteBeauty & Lifestyle Writer

Sneha is a relationships and lifestyle writer with a strong foundation in applied linguistics and certified training in relationship coaching. She brings over five years of writing experience to thebridalbox, crafting thoughtful, research-driven content that empowers readers to build healthier relationships, boost emotional well-being, and embrace holistic living.

Read full bio of Sneha Tete