Stomach ulcer. Coloured barium X-ray of a patient's stomach (blue/white) showing a gastric ulcer (pink, upper right). Benign gastric ulcers develop when digestive secretions in the stomach attack its lining. Certain factors promote ulcer formation, including aspirin and non-steroidal anti-inflammatory drugs, or the presence of the bacterium Helicobacter pylori. The symptoms of an ulcer include abdominal pain and vomiting blood. These are relieved by antacid drugs. Most ulcers heal if anti-secretory drugs are taken, but surgery to cut the vagal nerve (responsible for stomach acid production), or to remove part of the stomach, may be required in severe cases.