Peptic ulcer refers to the benign ulcer in the stomach and duodenum. The clinical presentation includes periodic and rhythmic epigastric pain accompanied with dyspeptic symptoms: acid regurgitation, belching, nausea, vomiting, etc. The ulcer of the stomach, 0.5-2.5 cm in diameter, is generally larger than that of the duodenum. In most cases, there is only one ulcerative focus; in a few cases there may be two ulcerative foci simultaneously, which is called complex ulcer.

Peptic ulcer is a frequently encountered disease and it may be found in 10%-12 % of the world's population. Most of the patients are young adults and there are more mate patients than female ones. Duodenal ulcer is more common than gastric ulcer and both of them last a long period of 10-20 years or even longer. If large quantity of bleeding, perforation, pylorochesis and cancerization occur, it is indicative of a critical condition with poor prognosis.