H. pylori Tests Explained: Breath, Stool, Blood or Endoscopy?

HealAlright Editorial Team · 14 October 2026 · 2 min read

Before treating H. pylori, it needs to be confirmed. The right test, done correctly, prevents unnecessary antibiotics and wasted money. Here is how the main options compare.

1. Urea breath test

You drink a special solution, then breathe into a bag or tube. If H. pylori is present, it breaks down the solution and releases a marker gas that the test detects.

Accuracy: very high
Good for: diagnosis and confirming a cure after treatment
Downside: not available everywhere

2. Stool antigen test

A small stool sample is tested for H. pylori proteins.

Accuracy: high (the monoclonal versions especially)
Good for: diagnosis and confirming a cure
Downside: some people find collecting a sample unpleasant

3. Endoscopy with biopsy

A thin camera is passed into the stomach and small tissue samples are taken.

Accuracy: very high
Good for: people who need an endoscopy anyway, such as those with warning signs, older age at first symptoms, or treatment failure, when antibiotic sensitivity testing may be useful
Downside: more invasive and more expensive

4. Blood antibody test

Shows whether your body has ever been exposed to H. pylori.

Limitation: antibodies can remain for years after the infection is gone, so a positive result does not prove a current infection, and the test cannot confirm a cure
Many guidelines advise against using it as the main test where breath or stool tests are available

Preparation matters

Some medicines suppress H. pylori and can cause false negative results. Doctors commonly advise, where safe:

Stopping proton pump inhibitors (such as omeprazole) for about two weeks before a breath or stool test
Avoiding antibiotics and bismuth for about four weeks before testing

Never stop a prescribed medicine without checking with your doctor.

After treatment

Confirm the result with a breath or stool test at least four weeks after finishing antibiotics. Feeling better is not proof the infection has gone.

Key takeaway

Breath and stool tests are accurate, simple and suitable for most people. Prepare properly, avoid relying on blood tests to judge a cure, and always confirm after treatment.

Medical disclaimer. This article is general health information, not medical advice, diagnosis or treatment. The HealAlright team are not doctors. Always talk to a qualified health professional about your symptoms and before starting, changing or stopping any medicine. If you vomit blood, pass black stools, feel faint or have sudden severe stomach pain, seek emergency care immediately.