Also called: H. pylori infections
Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.
About Helicobacter pylori Infections
Helicobacter pylori (H. pylori) is a type of bacteria that causes infection in the stomach. It is the main cause of peptic ulcers, and it can also cause gastritis and stomach cancer.
About 30 to 40% of people in the United States get an H. pylori infection. Most people get it as a child. H. pylori usually does not cause symptoms. But it can break down the inner protective coating in some people's stomachs and cause inflammation. This can lead to gastritis or a peptic ulcer.
Researchers aren't sure how H. pylori spreads. They think that it may spread by unclean food and water, or through contact with an infected person's saliva and other body fluids.
A peptic ulcer causes a dull or burning pain in your stomach, especially when you have an empty stomach. It lasts for minutes to hours, and it may come and go for several days or weeks. It may also cause other symptoms, such as bloating, nausea, and weight loss. If you have the symptoms of a peptic ulcer, your health care provider will check to see whether you have H. pylori. There are blood, breath, and stool tests to check for H. pylori. In some cases, you may need an upper endoscopy, often with a biopsy.
If you do have a peptic ulcer, the treatment is with a combination of antibiotics and acid-reducing medicines. You will need to be tested again after treatment to make sure the infection is gone.
There is no vaccine for H. pylori. Since H. pylori might spread through unclean food and water, you might be able to prevent it if you:
- Wash your hands after using the bathroom and before eating
- Eat properly prepared food
- Drink water from a clean, safe source
It sits within Digestive System and Infections.
The lead U.S. institute for this subject is the National Institute of Diabetes and Digestive and Kidney Diseases.
When to speak to someone. Reading about a topic cannot tell you whether it applies to you. Speak to a doctor or pharmacist if symptoms are severe, sudden, getting worse, or simply not going away — and seek emergency care immediately for chest pain, breathing difficulty, sudden weakness or confusion, or a serious allergic reaction.
Research on Helicobacter pylori Infections
640 studies areregistered for this condition on ClinicalTrials.gov, the U.S. National Library of Medicine's public registry. A selection is below — the links go straight to the registry entry, not to a summary of ours.
What a registered study does and does not mean. Registration means a study exists and has been declared publicly. It says nothing about whether the treatment being tested works, is safe, or is available to you. Many studies find no benefit — that is what research is for. Never seek out an experimental treatment on the strength of a registry entry alone.
Research currently under way
- Pylori Duo for Adjunctive Treatment and Prevention of Recurrence of Helicobacter Pylori InfectionGala Servicios Clinicos S.L.
- Helicobacter Pylori Infection Status and Pathological Features for Predicting Gastric Cancer Biological Behavior and Prognosis: A Real-World Observational StudyChinese PLA General Hospital
- Efficacy Comparison of 10-Day High-Dose Versus 14-Day Standard-Dose Vonoprazan Plus Amoxicillin in Helicobacter Pylori Eradication: A Multicenter Non-Inferiority Randomized Controlled TrialShandong University
- Study on the Effect of Fecal Microbiota Transplantation on Eradication of Refractory Helicobacter Pylori InfectionSichuan Provincial People's Hospital
- Application of Artificial Intelligence on the Diagnosis of Helicobacter Pylori Infection and Premalignant Gastric LesionNational Taiwan University Hospital
- Effect of PPIs on Stool DNA Test for H. PyloriShanghai Jiao Tong University School of Medicine
Research already completed
- H. Pylori Infection and Metabolic Syndrome: A Retrospective Cross-Sectional StudyNanjing First Hospital, Nanjing Medical University
- Tegoprazan and Amoxicillin Dual TherapySoonchunhyang University Hospital
Study data from ClinicalTrials.gov, a service of the U.S. National Library of Medicine. Retrieved 2026-07-30. Registry entries are supplied by study sponsors and investigators; ClinicalTrials.gov does not verify their scientific validity. PocketsInfo is not affiliated with, and not endorsed by, the NLM or the NIH.
Where to read more
Rather than paraphrase, we point you to the primary sources. Every link below is to a government health agency, a national institute or a recognised medical body — grouped by what you are trying to find out.
Start Here
- Helicobacter pylori InfectionsNemours Foundation
Diagnosis and Tests
- Helicobacter pylori (H. pylori) TestsNational Library of Medicine
- Stool Test: H. pylori AntigenNemours Foundation
Treatments and Therapies
- Helicobacter pylori (H. pylori) Infection: Diagnosis and TreatmentMayo Foundation for Medical Education and Research
Related Issues
- Gastritis and GastropathyNational Institute of Diabetes and Digestive and Kidney Diseases
Clinical Trials
- ClinicalTrials.gov: Helicobacter pylori InfectionsNational Institutes of Health
Medical subject headings
Clinicians and researchers index this subject under Helicobacter Infections. These are the terms to use when searching medical literature.
This page is built from the MedlinePlus health topic record for Helicobacter pylori Infections, a service of the U.S. National Library of Medicine (NLM), National Institutes of Health. Information is from MedlinePlus.gov. PocketsInfo is not affiliated with, and is not endorsed by, the NLM or the NIH. Retrieved 30 July 2026.