The Connection Between H. Pylori and Your Gut

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Helicobacter pylori — or H. pylori for short — is a spiral-shaped bacteria that thrives in acidic environments. It is common and affects approximately 50% of the world’s population. Most often, it lives in the stomach and small intestine and doesn’t cause any symptoms. But it is associated with an increased risk of ulcers in the stomach and the duodenum (the first part of the small intestine). And it can also lead to inflammation of the lining of the stomach, called gastritis.

Here, we’ll discuss the potential symptoms, diagnosis, and treatment of H. pylori.

Symptoms of H. pylori

While H. pylori is a bacteria that lives in the gut, it acts differently than a typical bacterial infection does. In fact, most people who have H. pylori don’t have any symptoms. But when H. pylori leads to inflammation or ulcers in the stomach lining, these conditions can cause symptoms such as:

• Burning or dull pain in the upper portion of the abdomen

• Pain that’s worse on an empty stomach or a few hours after eating, but improves with food or antacids

• Burping or an acidic taste in the mouth

• Nausea

• Bloating

• Discomfort after eating and decreased appetite, which can cause weight loss

Ulcers caused by H. pylori can also cause gastrointestinal (GI) bleeding. When an ulcer bleeds, it can lead to: 

• Dark, tarry stool

• Vomiting bright-red or clotted blood (sometimes appearing like coffee grounds)

• Low blood cell counts

• Increased fatigue or shortness of breath

Who should get tested for H. pylori?

Although H. pylori is fairly common, experts recommend that only people who meet certain criteria are tested. Testing for H. pylori is recommended for people who have or have a history of:

• Symptoms of H. pylori

• Peptic ulcer disease

• Stomach cancer

• Long-term use of nonsteroidal anti-inflammatory drugs (NSAIDs) or aspirin

• Unexplained iron-deficiency anemia (a shortage of iron leading to low blood cell counts)

• Immune thrombocytopenia (a platelet disorder that can be associated with H. pylori)

Testing is also recommended for first-generation immigrants from areas with a high prevalence of H. pylori, which includes many African countries, China, Japan, and Eastern European countries.

Is H. pylori contagious?

H. pylori transmission is still the subject of ongoing research. But experts think that it’s most likely spread: 

• Through contaminated food and water

• Directly from person to person, via transmission in saliva or feces (eating food that was handled by someone with H. pylori who didn’t wash their hands after using the bathroom) 

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People who grow up in low-income or developing countries are especially at risk due to differences in sanitation. Most people who grow up in these environments and acquire the infection do so as children. In the US, by contrast, most people who acquire the infection do so as adults. 

How is H. pylori diagnosed?

There are three main tests that can be used to diagnose H. pylori, and each one has some pros and cons:

1. The urea breath test: This involves drinking a solution that contains a compound called urea, followed by breathing into a bag. H. pylori is detected by the way it breaks down the urea. This test is the most accurate, but it’s also the most expensive. And it requires that you don’t take any antibiotics or proton pump inhibitors (PPIs) for a few weeks prior to testing.

2. The fecal antigen test: This is a stool test that looks for signs of H. pylori. This test is almost as accurate as the urea breath test, and it’s much less expensive. It also requires that you don’t take any antibiotics or PPIs for a few weeks before the test.

3. A serologic blood test: This checks for antibodies to H. pylori in the blood. This test is not usually recommended because it’s difficult to tell if someone has an active infection or if they were only exposed in the past. But it is the only test that does not require someone to be off all antibiotics and PPIs for several weeks prior.

Most people don’t need an endoscopy to diagnose and treat H. pylori. But if there are indications that you need an endoscopy, your provider can diagnose H. pylori by taking a biopsy sample during the procedure. 

H. pylori treatment

Treatment for H. pylori involves taking multiple medications, usually for 10 to 14 days total. There are several different regimens and medication combinations that can be used. But they typically include:

• A PPI, such as pantoprazole or omeprazole

• Two or three different antibiotics, which may involve a combination of clarithromycin, amoxicillin, metronidazole, tetracycline, or levofloxacin

• Bismuth subsalicylate (more commonly known as Pepto-Bismol)

The decision about which antibiotics are included in a regimen depends on what treatments have been tried before (if any), the presence of any allergies, and what the local H. pylori bacteria in your region are susceptible to.

The reason that multiple antibiotics are needed is because H. pylori is good at guarding itself against treatment and is usually resistant to one or two medications. That’s why it’s important to complete the full course of treatment, even if your symptoms improve after a few days. Otherwise, some H. pylori bacteria may remain and grow after you stop the treatment. 

Even if you complete the full treatment course, H. pylori can still come back. So your provider will usually recommend that you get retested a few weeks after you complete the treatment to make sure that it worked. 

If the treatment is not initially successful, your provider will recommend a different regimen that may work better against the specific H. pylori bacteria causing your infection.

What happens if H. pylori goes untreated?

Untreated H. pylori is a risk factor for ulcers in the stomach and duodenum. In fact, H. pylori is one of the main causes of these ulcers. And it can also cause inflammation of the stomach lining, called gastritis. 

When someone has H. pylori living in their digestive for a long period of time, it can increase their risk for developing two different, rare types of stomach cancer:

1. Gastric adenocarcinoma

2. Gastric mucosa-associated lymphoid tissue (MALT) lymphoma

It’s important to treat H. pylori infection before it can cause any complications. 

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Written by:

Joanna Jan, MD

Joanna Jan, MD, is board-certified in internal medicine and licensed to practice medicine in the state of Pennsylvania. In 2017, she received her board certification from the American Board of Internal Medicine.

Edited by:

Katie E. Golden, MD

Katie E. Golden, MD, is a board-certified emergency medicine physician and a medical editor at GoodRx.

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