Helicobacter pylori (H. pylori) is a common bacterium that often infects the stomach during childhood. On its own, the infection typically causes no noticeable symptoms. Many people may carry the bacteria without ever knowing it, and it's estimated that 30–40% of people in the United States are infected.

While H. pylori doesn’t always lead to complications, experts have identified it as the primary cause of peptic ulcers. These ulcers form in the lining of the stomach or the duodenum—the first part of the small intestine—and may lead to symptoms such as burning abdominal pain, nausea, vomiting, and weight loss. These signs can appear gradually, worsen over time, or fluctuate in intensity.

Although most people with H. pylori do not experience complications, others may develop ulcers, gastrointestinal disorders, or, in rare cases, stomach cancer. If you experience symptoms related to ulcers, it’s important to consult a healthcare provider for testing and treatment.

Burning stomach pain

irritation of the stomach lining
The protective mucosal lining in your stomach can be weakened by H. pylori, making it prone to ulcer formation. A frequent symptom of peptic ulcers is dull or burning pain in the upper abdomen. This discomfort may occur on an empty stomach, though some people feel it more intensely after eating.

Upset stomach

nausea and vomiting
Gastric ulcers located in the stomach often result in nausea and vomiting. Duodenal ulcers, found in the upper small intestine, may also trigger these symptoms.

nsaids can worsen symptoms
Taking medications such as ibuprofen or naproxen can aggravate ulcer-related pain. Be sure to inform your healthcare provider if you take NSAIDs and experience ongoing abdominal discomfort.

Bloating

increased gas and fullness
Ulcers can cause excess gas or air to build up in your digestive tract, leading to bloating or burping. These symptoms often occur after meals and may reduce your appetite.

Loss of appetite

early satiety
If you feel full quickly after eating a small amount of food or are unable to eat more without discomfort, this may signal an ulcer. This condition, known as early satiety, can contribute to poor nutrition over time.

Weight loss

eating less due to discomfort
Many people with ulcers reduce their food intake because of pain, nausea, or bloating. This can lead to unintended weight loss. Seek immediate medical attention if persistent vomiting is contributing to your weight loss.

Symptoms in children

same symptoms as adults
H. pylori infections often begin in childhood, though symptoms are typically absent. When children do experience symptoms, they are similar to those in adults—stomach pain, bloating, nausea, vomiting, burping, and poor appetite.

When to see a healthcare provider

testing and treatment
If you experience any signs of a peptic ulcer, schedule a visit with your provider. H. pylori can be detected using blood, breath, or stool tests. If the infection is confirmed, treatment usually includes a combination of two or more antibiotics and acid-reducing medications, such as proton pump inhibitors (e.g., Prilosec or Nexium) or bismuth-based therapies like Pepto-Bismol.

Emergency symptoms

serious complications
Untreated ulcers can cause complications like bleeding, perforation, or blockages. Seek urgent care if you experience:

  • Black, tarry, or bloody stools

  • Vomit containing blood or resembling coffee grounds

  • Intense, persistent stomach pain

  • Dizziness or fainting

  • Rapid heart rate

Cancer risk

long-term infection complications
In rare cases, chronic H. pylori infection may increase the risk of developing stomach or esophageal cancer. Although these cancers are uncommon, H. pylori is considered a major contributing factor.

possible cancer symptoms
If you notice signs like ongoing belly pain, poor appetite, bloody stool, persistent vomiting, chronic cough, hoarseness, or trouble swallowing, contact your provider as soon as possible for further evaluation.

A quick review

H. pylori infection is widespread and often asymptomatic. However, it can lead to peptic ulcers and, in rare cases, more serious conditions like cancer. If you experience signs of a peptic ulcer—such as burning pain, bloating, nausea, vomiting, or appetite changes—consult a healthcare professional. They can confirm the presence of H. pylori and begin appropriate treatment to reduce symptoms and prevent complications.