Most people with ulcers just have stomach pain. Some people don't have any symptoms at all. But ulcers may cause other health problems. Sometimes they bleed. If the ulcers become too deep, they can break through the stomach.
Ulcers can block food from going through the intestines.
This causes nausea, vomiting and weight loss. Doctors used to think ulcers were caused by stress or by eating food with too much acid in it. We now know this isn't true. We now know that most stomach ulcers are caused by an infection. About half of the world's population is infected with H. pylori.