Clinical Definition

A peptic ulcer is an ulceration of the alimentary mucosa. It usually develops in the duodenum or the stomach, which are exposed to gastric secretions. An infection with the bacterium Helicobacter pylori is believed to contribute to a large percentage of peptic ulcers.

In Our Own Words

A peptic ulcer is a lesion or sore in the mucus membrane or lining of the stomach. It can also occur in the first section of the small intestine, known as the duodenum. Normally, the stomach and intestines have a layer of mucus, which protects the cells in the lining from stomach acid. Certain factors can cause the amount of mucus to decrease, which leaves the lining of the stomach and duodenum more susceptible to injury from digestive juices.

In the past, it was thought ulcers were caused by stress. Current research has indicated a large percentage of peptic ulcers are due to an infection with the bacteria H. pylori. These bacteria are believed to decrease the effectiveness of the protective mucus in the stomach.