A duodenal ulcer is a form of peptic ulcer disease. It is defined by a mucosal defect extending through the muscularis mucosa in the intestinal lining. Duodenal ulcers are at risk for eroding into blood vessels, leading to gastrointestinal bleeding.

NSAIDs are a common cause of duodenal ulcer. Mucosal injury due to chronic infection from Helicobacter pylori may be a cause. Smoking is a strong risk factor for developing ulcers. There are other much less common causes including Zollinger-Ellison syndrome.

Patients can present with a variety of symptoms from duodenal ulcers. Epigastric abdominal pain and dyspepsia are most common. If eroded into a blood vessel, hematemesis, melena, or rarely bright red blood per rectum (if there is brisk bleeding) can be presenting symptoms.

Helicobacter pylori is a common worldwide infection predisposing to duodenal ulcers. Untreated, it is also a carcinogen associated with the development of gastric cancer.

Patients with concern for a duodenal ulcer, whether bleeding or not bleeding, should undergo an esophagogastroduodenoscopy (EGD) to confirm the diagnosis.