Peptic ulcer disease occurs when the lining of the esophagus, stomach, or duodenum is worn away. The damage may be caused by stomach acid or other factors.

What is going on in the body?

Peptic ulcer disease most commonly occurs in the upper part of the small intestine, called the duodenum. It also occurs in the stomach. Ulcers less commonly occur in the esophagus. The esophagus is the food tube that connects the mouth to the stomach.

What are the causes and risks of the condition?

Stomach acid is thought to play a role in causing peptic ulcer disease. A bacterial infection known as Haemophilus pylori may also be important in causing a person's ulcer. Ulcers may also be caused by the use of certain pain medicines. Each of these factors breaks down the natural protective lining of the digestive tract. Inherited factors are also thought to play a role in ulcer formation.