A peptic ulcer is a defect in the gastric or duodenal wall that extends through the muscularis mucosa and into the deep layers of the wall. Approaches to peptic ulcer disease (PUD) have changed throughout the years. As with most diseases, knowing the cause of an ulcer remains the most important factor in deciding the treatment course and determining the prognosis. If an ulcer develops in a patient who is known to be achlorhydric, a gastric malignancy is the likely cause for the ulceration. There are marked differences in the incidence of gastric and duodenal ulcers. Esophagogastroduodenoscopy (EGD) is considered the gold standard for evaluating lesions and abnormalities of the upper gastrointestinal (GI) tract. Patients may recognize some of the foods that seem to exacerbate their symptoms, but they should be educated about all offending agents. Smoking cessation cannot be overemphasized.