If ulcers aren't treated, serious complications may occur.
Bleeding
As an ulcer erodes the muscles of the stomach or duodenal wall, blood vessels may also be damaged, which causes the bleeding. If the affected blood vessels are small, the blood may slowly seep into the digestive tract. Over a long period of time, a person may become anemic. If a damaged blood vessel is large, bleeding is dangerous and requires prompt medical attention. The symptoms of this includes feeling weak and dizzy when standing, vomiting blood, or fainting. The stool may become a tarry, black color from the blood.Perforation
Sometimes an ulcer eats a hole in the wall of the stomach or duodenum. Bacteria and partially digested food can spill through the opening into the sterile abdominal cavity (peritoneum). This causes peritonitis, an inflammation of the abdominal cavity and wall. The symptoms of a perforated ulcer include cause sudden, sharp, severe pain.Narrowing and obstruction
Ulcers located at the end of the stomach where the duodenum is attached may cause swelling and scarring. This can narrow or close the intestinal opening, and can prevent food from leaving the stomach and entering the small intestine. As a result, a person may vomit the contents of the stomach.
