Most peptic ulcers are caused by the following:
- Helicobacter pylori (H. pylori), a germ that causes infection
- Nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin and ibuprofen
H. pylori is the most common cause of peptic ulcers. Doctors think H. pylori may be spread through unclean food or water or by mouth-to-mouth contact, such as kissing. Even though many people have an H. pylori infection, most of them never develop an ulcer.
Use of NSAIDs is the second-most common cause of peptic ulcers. But not everyone who takes NSAIDs gets a peptic ulcer. Ulcers caused by NSAIDs are more often found in people who:
- Are age 60 or older
- Are female
- Have taken NSAIDs for a long time
- Have had an ulcer before
Other causes of peptic ulcers are rare. One rare cause is Zollinger-Ellison syndrome -- a disease that makes the body produce too much stomach acid, which harms the lining of the stomach or duodenum.
Stress or spicy food does not cause peptic ulcers, but either can make ulcers worse and keep them from healing. This answer is based on source information from the National Institute of Diabetes and Digestive and Kidney Diseases.