Update Date: 14.06.2025
A Helicobacter pylori infection is a common stomach infection. It's caused by a germ called Helicobacter pylori, a bacteria also known as H. pylori.
More than half the people in the world may have an H. pylori infection at some point in their lives. These infections often happen during childhood, especially in developing countries. H. pylori germs seem to spread through contact with an infected person's bodily fluids, including vomit, stool or saliva. This includes contact that happens through poor hand hygiene. The germs also can spread through tainted food and water.
H. pylori infections can cause stomach pain, bloating, gas and other symptoms. But most people who become infected don't have symptoms. Sometimes, H. pylori infections lead to sores called peptic ulcers in the lining of the stomach or small intestine. Much less often, these infections can lead to stomach cancer.
Your healthcare professional likely will test you for an H. pylori infection if you get symptoms of a peptic ulcer. Treatment for the infection includes medicines called antibiotics to clear up the bacteria.
Help prevent an H. pylori infection by not sharing food or utensils.
Most H. pylori infections don't cause symptoms. When a person gets symptoms, they often come from swelling of the stomach lining or a peptic ulcer. The symptoms can include:
Make an appointment with your healthcare professional if you have ongoing stomach pain or other stomach symptoms. Get medical help right away for:
H. pylori infections are caused by H. pylori germs that get into the stomach lining. The germs appear to be passed from person to person through contact with saliva, vomit or stool. They also may be spread through contaminated surfaces, or tainted food or water.
Risk factors for H. pylori infections include your living conditions, health history and eating habits. These risk factors include:
An H. pylori infection can lead to other health conditions called complications. These can include:
You may be able to help prevent an H. pylori infection by not sharing food or utensils with family or friends.
Diagnosis of an H. pylori infection involves testing to find out if your symptoms are caused by H. pylori germs. Your healthcare professional may recommend one or more of the following tests:
A lab checks a sample of your stool for signs of H. pylori germs. These tests include:
You might hear this called a urea breath test. During the test, you swallow a pill, liquid or pudding that contains tagged carbon molecules in a substance called urea. If you have an H. pylori infection, carbon is released when the solution makes contact with the germs. This breaks down the urea, releasing the carbon.
Because your body absorbs the carbon, it is released when you breathe out. To measure the release of carbon, you blow into a bag. A device detects the carbon molecules to find out if more are released after taking the substance that contains urea. This test can be used for adults and children older than 6 who can follow along with the test instructions.
This test checks your upper digestive system. It's also called an upper endoscopy exam. Your healthcare professional may recommend it to check on symptoms that may be caused by a peptic ulcer or gastritis. These and certain other conditions can stem from H. pylori infections.
For this exam, you're given medicine to help you relax. Then, your healthcare professional threads a camera attached to a long, flexible tube down your throat and esophagus. This tool is called an endoscope.
The endoscope goes into your stomach and the first part of the intestine, called the duodenum. It lets your healthcare professional view any issues in your upper digestive tract. Your healthcare professional also might use the endoscope to take tissue samples. This is called a biopsy. These samples are checked by a lab for an H. pylori infection.
An upper endoscopy is more invasive than a breath or stool test. So it's often not used to diagnose an H. pylori infection alone. Healthcare professionals may use an upper endoscopy for further testing and to look for other digestive conditions. They also can use this test to figure out exactly which antibiotic is best to treat H. pylori infection, especially if the first antibiotics tried didn't get rid of the infection.
This test may need to be done again after treatment for an H. pylori infection. It depends on what is found at the first endoscopy or if your symptoms continue after treatment.
The same tests used for diagnosis can be used to tell if the H. pylori infection is gone after treatment. In general, you wait at least four weeks after you finish your antibiotic treatment to get these follow-up tests.
If your treatment includes certain other medicines, you'll also need to wait up to two weeks before follow-up testing. These medicines can affect the accuracy of the test results and include:
Your healthcare professional gives you specific instructions about your medicines.
In places where H. pylori infections and their complications are common, healthcare professionals sometimes test healthy people for H. pylori. This is called screening. Whether there is a benefit to this testing when you have no symptoms of infection is controversial among experts.
If you're concerned about an H. pylori infection, talk with your healthcare professional. Together you can decide whether H. pylori testing might be right for you. For example, your healthcare professional may recommend screening if you have a high risk of stomach cancer. Treatment may lower the chances that a stomach ulcer caused by an H. pylori infection becomes cancerous.
Treatment for H. pylori infections usually involve taking at least two different antibiotics at once. This helps prevent the germs from resisting the effects of one particular antibiotic.
Treatment also may include medicine to help your stomach heal, such as:
Follow-up testing for H. pylori at least four weeks after your treatment is recommended. If the tests show that the treatment didn't work, you may need more treatment with a different mix of antibiotics.
See your healthcare professional if you have symptoms of an H. pylori infection. Your healthcare team may test and treat you for H. pylori infection. Or you might be referred to a healthcare professional called a gastroenterologist, who treats diseases of the digestive system.
Here's some information to help you get ready for your healthcare appointment, and what to expect.
At the time you make the appointment, ask if there's anything you need to do in advance. For example, you might be told to restrict your diet.
Also, preparing a list of questions to ask may help you make the most of your time with your healthcare professional. Questions to ask include:
Feel free to ask any other questions during your appointment.
Your healthcare professional is likely to ask you questions such as:
Be ready to provide information and answer questions. It may give you more time to cover other points you want to talk about with your healthcare team.
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