Peptic ulcer disease is characterized by sores, or ulcerations, in the lining tissues of the stomach or the duodenum, the first portion of the small intestine. The primary symptom of peptic ulcer is upper abdominal pain. The pain can be sharp or dull and is often described as burning. Some affected people have indigestion that may quickly resolve after taking antacids or eating foods that neutralize stomach acids. Other people with peptic ulcers may not have symptoms at all or may have only very mild symptoms. The severity of the ulcers is not related to the severity of the symptoms they cause; mild ulcers may cause severe pain, while severe ulcers may only cause mild symptoms.

Loss of appetite and weight loss may occur in people with peptic ulcer disease. In certain cases, the ulcers may bleed into the gastrointestinal tract, resulting in dark (black or tarry) stool.

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