Helicobacter pylori (H pylori) is a type of bacteria that infects the stomach. It is very common, affecting about two thirds of the world's population. H pylori infection is the most common cause of peptic ulcers. However, the infection does not cause problems for most people.
H pylori bacteria are most likely passed directly from person to person. This tends to happen during childhood. The infection remains throughout life if not treated.
It's not clear how the bacteria are passed from one person to another. The bacteria may spread from:
The bacteria may trigger ulcers in the following way:
Besides ulcers, H pylori bacteria can also cause a chronic inflammation in the stomach (gastritis) or the upper part of the small intestine (duodenitis).
H pylori can also sometimes lead to stomach cancer or a rare type of stomach lymphoma.
About 10% to 15% of people infected with H pylori develop peptic ulcer disease. Small ulcers may not cause any symptoms. Some ulcers can cause serious bleeding.
An aching or burning pain in your abdomen is a common symptom. The pain may be worse with an empty stomach. The pain can differ from person to person, and some people have no pain.
Other symptoms include:
Your health care provider will test you for H pylori if you:
Tell your provider about the medicines you take. The nonsteroidal anti-inflammatory drugs (NSAIDs) can also cause ulcers. If you show the symptoms of infection, the provider may perform following tests for H pylori. These include:
In order for your ulcer to heal and to reduce the chance it will come back, you will be given medicines to:
Take all of your medicines as you have been told. Other lifestyle changes can also help.
If you have a peptic ulcer and an H pylori infection, treatment is recommended. The standard treatment involves different combinations of the following medicines for 10 to 14 days:
Taking all of these medicines for up to 14 days is not easy. But doing so gives you the best chance for getting rid of the H pylori bacteria and preventing ulcers in the future.
If you take your medicines, there is a good chance that the H pylori infection will be cured. You will be much less likely to get another ulcer.
Sometimes, H pylori can be hard to fully cure. Repeated courses of different treatments may be needed. A stomach biopsy will sometimes be done to test the germ to see which antibiotic might work best. This can help guide future treatment. In some cases, H pylori can't be cured with any therapy, though the symptoms may be able to be reduced.
If cured, reinfection may occur in areas where sanitary conditions are poor.
A long-term (chronic) infection with H pylori may lead to:
Other complications may include:
Severe symptoms that begin suddenly may indicate a blockage in the intestine, perforation, or hemorrhage, all of which are emergencies. Symptoms may include:
Anyone who has any of these symptoms should go to the emergency room right away.
Reviewed By: Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School; Assistant in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, MA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.