Patient education: Helicobacter pylori infection and treatment (Beyond the Basics)

HELICOBACTER PYLORI OVERVIEW — 

Helicobacter pylori, also known as H. pylori, is a bacterium that is commonly found in the stomach. It is present in approximately one-half of the world's population.

The vast majority of people worldwide who have H. pylori get the infection as children. Most have no symptoms and will never develop problems. However, H. pylori is capable of causing several digestive problems, including dyspepsia (abdominal pain), ulcers, and, very rarely, stomach cancer. It is not clear why some people with H. pylori get these conditions and others do not.

This article discusses the symptoms, testing, and treatment of H. pylori infections. Stomach ulcers, also known as peptic ulcers, are discussed separately. (See "Patient education: Peptic ulcer disease (Beyond the Basics)".)

H. PYLORI RISK FACTORS — 

Most cases of H. pylori are likely spread from person to person by the "fecal-oral" route. This is when bacteria are present in a person's feces and then infect another person by entering through the mouth, often by consuming contaminated food or water.

Most people get infected with H. pylori during childhood due to spread of the infection within the family or home. H. pylori infection typically persists unless it is treated with anti-H. pylori medications. Consequently, areas with high rates of childhood infection will typically have high infection rates in adults when those children age. Similarly, people who grow up in areas with lower rates of childhood infection will typically have lower infection rates in adults. This is known as the "birth cohort" effect.

H. PYLORI'S EFFECTS ON THE STOMACH — 

H. pylori causes changes to the lining of the stomach and duodenum (the first part of the small intestine) (figure 1). The bacteria colonize the cells that line the stomach. This leads to the release of certain enzymes and toxins and activation of the immune system. Together, these factors can injure the cells of the stomach or duodenum. This causes chronic inflammation in the stomach (gastritis) and/or duodenum (duodenitis).

As a result of these changes, the stomach and duodenum are more vulnerable to damage from digestive juices, such as stomach acid. In some people, H. pylori can increase the production of stomach acid, which can further injure the stomach lining and cause ulcers.

H. PYLORI SYMPTOMS — 

Most individuals with chronic gastritis or duodenitis caused by H. pylori have no symptoms. However, approximately 5 to 10 percent of people develop more serious problems, including stomach or duodenal ulcers and, rarely, stomach cancer.

Ulcers can cause a variety of symptoms or no symptoms at all. The most common ulcer symptoms include:

●Pain or discomfort (usually in the upper abdomen)

●Feeling full after eating a small amount of food

●Nausea or vomiting

●Black, tarry stools (if ulcers bleed)

●Fatigue (if ulcers bleed enough to cause a low blood count) (see "Patient education: Peptic ulcer disease (Beyond the Basics)")

Less commonly, chronic gastritis causes abnormal changes in the stomach lining, which can lead to precancerous changes (such as "intestinal metaplasia" and "dysplasia") and, rarely, stomach cancer. Fewer than 3 percent of people with H. pylori infection develop gastric cancer as a result of the infection. Nevertheless, because so many people in the world are infected, H. pylori is the leading cause of infection-associated cancer in the world.

H. PYLORI DIAGNOSIS — 

There are several ways to diagnose H. pylori. The most commonly used tests include the following:

Breath tests — Breath tests (known as urea breath tests) require that you drink a specialized solution containing a substance that is broken down by the H. pylori bacteria. The breakdown products can be detected in your breath.

Stool tests — Tests are available that detect H. pylori in stool.

Tests of biopsy samples — Biopsy specimens from the stomach can also be tested for H. pylori. For a biopsy, a doctor takes a small piece of tissue from the lining of the stomach during an upper endoscopy. An upper endoscopy is an examination that uses a thin tube with a camera on the end to see inside the stomach and duodenum. Biopsy is used in people who already need an upper endoscopy to evaluate their symptoms or treat a peptic ulcer.

Blood tests — Blood tests can detect specific antibodies (proteins) that the body's immune system develops in response to the presence of H. pylori bacteria in the stomach lining. This blood test can stay positive even after H. pylori has been successfully treated. As a result, it does not accurately differentiate between past and current H. pylori infection. Consequently, blood tests are not recommended for initial diagnosis or follow-up testing.

WHO SHOULD BE TESTED FOR H. PYLORI?

If you have symptoms — Diagnostic testing for H. pylori infection is recommended if you have chronic stomach pain, nausea, active gastric/duodenal ulcers, a past history of ulcers, or certain abnormal blood counts (eg, low platelets or anemia caused by iron deficiency).

Although H. pylori infection is the most common cause of ulcers, not all patients with ulcers have H. pylori. Certain medications (eg, aspirin, ibuprofen [Motrin, Advil], naproxen [Aleve]) can also cause peptic ulcers. (See "Patient education: Peptic ulcer disease (Beyond the Basics)".)

If you do not have symptoms but have an increased risk of H. pylori complications — H. pylori testing is usually not recommended if you have no symptoms and no past history of peptic ulcer disease or gastric precancer/cancer. However, it may be considered for selected people, such as adults with a family history of gastric cancer, household contacts of someone with H. pylori infection, immigrants from countries where rates of H. pylori infection and gastric cancer are high, and those of certain non-White races or ethnicities. Guidelines in the United States and other countries also recommend H. pylori testing for people who require treatment with long-term anti-inflammatory medications (nonsteroidal anti-inflammatory drugs, or "NSAIDs"), such as aspirin, ibuprofen, naproxen, and similar drugs.

H. PYLORI TREATMENT — 

All individuals with H. pylori infection should be treated unless there are contraindications, such as pregnancy or limited life expectancy.

Importantly, H. pylori eradication can reduce the risk of developing gastric cancer. In people with peptic ulcers, successful treatment of H. pylori also helps ulcers heal, prevents ulcers from coming back, and reduces the risk of ulcer complications (like bleeding). In people who take long-term anti-inflammatory medications, treatment for H. pylori can help prevent stomach ulcers and other complications.

Medications — No single drug cures H. pylori infection. Most treatment regimens involve taking two to four medications for 14 days.

●Most treatment regimens include either a medication called a proton pump inhibitor (PPI) or a potassium-competitive acid blocker (PCAB). These medications decrease the stomach's production of acid, which helps certain antibiotics work more effectively. Examples of PPIs include lansoprazole (brand name: Prevacid), omeprazole (brand name: Prilosec), pantoprazole (brand name: Protonix), rabeprazole (brand name: AcipHex), dexlansoprazole (brand name: Dexilant), and esomeprazole (brand name: Nexium). An example of a PCAB is vonoprazan (brand name: Voquezna).

●Other components of treatment include at least one antibiotic. In an increasing number of cases, H. pylori infection is or becomes resistant to antibiotics. For this reason, it is important to take all the medications prescribed for the entire course. Although most regimens are 14 days, one regimen (brand name: Pylera) comes as a prepacked 10-day course.

Side effects — Up to 50 percent of patients have side effects while taking H. pylori treatment. Side effects are usually mild, and fewer than 10 percent of patients stop treatment because of side effects.

It is important to inform your health care provider if you experience side effects. It may be possible to make adjustments in the dose or timing of medication or take other medicines to help with side effects like nausea. Some of the most common side effects are described below:

●Some of the treatment regimens use a medication called metronidazole (brand name: Likmez) or clarithromycin (brand name: Biaxin). These medications can cause a metallic taste in the mouth and nausea.

●Alcoholic beverages (including beer, wine, and liquor) should be avoided while taking metronidazole; the combination can cause skin flushing, headache, nausea, vomiting, sweating, and a rapid heart rate.

●Bismuth, which is often used to treat H. pylori, may cause constipation. It can also cause the tongue and stool to temporarily look black.

●Many of the regimens cause diarrhea and stomach cramps.

Follow-up — After completing H. pylori treatment, it is important to have repeat testing to ensure that the infection has been successfully treated. This is typically done with a breath or stool test (see 'H. pylori diagnosis' above). Testing should be done at least four weeks after completing treatment. It is important to avoid taking a PPI or PCAB for two weeks before the test because these medications may cause a "false-negative" result.

Treatment failure — Up to 20 percent of persons with H. pylori infection are not cured after their first course of treatment. These people need "retreatment" with a second course of H. pylori medication. Retreatment typically requires a different regimen than was taken with the first treatment course.

SUMMARY

●Helicobacter pylori, also known as H. pylori, is a bacterium that causes a chronic infection of the stomach. This infection causes inflammation of the stomach lining, but most people infected with H. pylori have no symptoms or serious problems. However, some people develop complications such as stomach ulcers and, rarely, stomach tumors.

●Ulcers may cause no symptoms or may cause pain or discomfort (usually in the upper abdomen), feeling full after eating a small amount of food, nausea, or vomiting. Ulcers that bleed can cause black, tar-like stools or a low blood count.

●H. pylori is diagnosed by a stool test or breath test or sometimes during an upper endoscopy.

●H. pylori testing is recommended for anyone with a peptic (stomach or duodenal) ulcer or chronic stomach pain or nausea.

●Anyone diagnosed with H. pylori should be treated, whether they are having symptoms or not. Successful treatment lowers the risk of developing stomach (gastric) cancer.

In people with stomach or duodenum ulcer(s), H. pylori treatment helps to heal ulcers, lowers the risk that ulcers will return, and lowers the risk of bleeding or other complications from the ulcers.

●H. pylori treatment usually includes up to four medicines. At least one of the medicines is an antibiotic that helps to kill the bacteria. Another medication causes the stomach to make less acid.

●Most, but not all, people are cured after finishing two weeks of medicine. It is important to finish all of the medicine as instructed to ensure that the bacteria are killed.

●All people treated for H. pylori should undergo a breath or stool test at least four weeks after finishing the medication. This is done to be sure that the bacteria were killed. Ideally, the test is done after the person has been off proton pump inhibitor and potassium-competitive acid blocker medications for two weeks.

●If the repeat test shows that the H. pylori bacteria are still present, then another two weeks of a different treatment regimen will be necessary.

WHERE TO GET MORE INFORMATION — 

Your health care provider is the best source of information for questions and concerns related to your medical problem.

This article will be updated as needed on our website (www.uptodate.com/patients). Related topics for patients, as well as selected articles written for health care professionals, are also available. Some of the most relevant are listed below.

Patient level information — UpToDate offers two types of patient education materials.

The Basics — The Basics patient education pieces answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials.

Patient education: H. pylori infection (The Basics)
Patient education: H. pylori tests (The Basics)
Patient education: Peptic ulcers (The Basics)
Patient education: Stomach polyps (The Basics)
Patient education: Stomach cancer (The Basics)

Beyond the Basics — Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are best for patients who want in-depth information and are comfortable with some medical jargon.

Patient education: Peptic ulcer disease (Beyond the Basics)

Professional level information — Professional level articles are designed to keep doctors and other health professionals up-to-date on the latest medical findings. These articles are thorough, long, and complex, and they contain multiple references to the research on which they are based. Professional level articles are best for people who are comfortable with a lot of medical terminology and who want to read the same materials their doctors are reading.

Helicobacter pylori: Epidemiology, pathophysiology, and overview of disease associations
Approach to the diagnosis of Helicobacter pylori infection in adults
Treatment of Helicobacter pylori infection in adults
Acute and chronic gastritis due to Helicobacter pylori
Helicobacter pylori and gastroesophageal reflux disease
Peptic ulcer disease: Clinical manifestations and diagnosis
Peptic ulcer disease: Treatment and secondary prevention
Unusual causes of peptic ulcer disease

The following organizations also provide reliable health information.

●National Library of Medicine

(www.nlm.nih.gov/medlineplus/healthtopics.html)

●National Institute of Diabetes and Digestive and Kidney Diseases

(www.niddk.nih.gov/)

●Centers for Disease Control and Prevention (CDC)

(www.cdc.gov/)

●The American Gastroenterological Association

(gastro.org)

●The American College of Gastroenterology (ACG)

(https://gi.org/)

ACKNOWLEDGMENTS

The UpToDate editorial staff acknowledges Sheila E Crowe, MD, FRCPC, FACP, FACG, AGAF, who contributed to earlier versions of this topic review.

We are saddened by the death of Mark Feldman, MD, who passed away in March 2024. UpToDate gratefully acknowledges Dr. Feldman's role as a Section Editor on this topic and his dedicated and longstanding involvement with the UpToDate program.