A peptic ulcer is erosion in the lining of the stomach or the first part of the small intestine, an area called the duodenum.

If the peptic ulcer is located in the stomach it is called a gastric ulcer.

See also:

• Gastritis
• Gastroesophageal reflux disease (GERD)

Normally, the lining of the stomach and small intestines are protected against the irritating acids produced in your stomach. If this protective lining stops working correctly, and the lining breaks down, it results in inflammation (gastritis) or an ulcer.

Most ulcers occur in the first layer of the inner lining. A hole that goes all the way through the stomach or duodenum is called a perforation. A perforation is a medical emergency.

The most common cause of such damage is infection of the stomach by bacteria called Helicobacter pylori (H.pylori). Most people with peptic ulcers have these bacteria living in their gastrointestinal (GI) tract. Yet, many people who have such bacteria in their stomach do not develop an ulcer.

The following also raise your risk for peptic ulcers:

• Drinking too much alcohol
• Regular use of aspirin, ibuprofen, naproxen, or other nonsteroidal anti-inflammatory drugs (NSAIDs). Taking aspirin or NSAIDs once in awhile is safe for most people.
• Smoking cigarettes or chewing tobacco
• Being very ill, such as being on a breathing machine
• Radiation treatments

A rare condition called Zollinger-Ellison syndrome causes stomach and duodenal ulcers. Persons with this disease have a tumor in the pancreas that releases high levels of a hormone, which causes an increase in stomach acid.

Many people believe that stress causes ulcers. It is not clear if this is true, at least for everyday stress at home.