Skip to Main Content
Diagnosis Gastroenterology


Your doctor may first perform an upper gastrointestinal (GI) series and endoscopy to check for ulcers.

An upper GI series involves X-rays of the esophagus, stomach and the beginning of the small intestine, called the duodenum. You will be asked to drink a chalky liquid, called barium, to make these organs appear more clearly on the X-ray.

During an endoscopy, the upper portion of the gastrointestinal tract is visualized by using a long, thin and flexible tube with a tiny video camera and light on the end, called an endoscope. The areas examined during this procedure include the esophagus, or the swallowing tube leading to the stomach, the stomach and the duodenum. The high-quality picture from the endoscope is shown on a television monitor and provides a clear, detailed view. In many cases, upper GI endoscopy is a more precise examination than X-ray studies.

This procedure is performed by a gastroenterologist, a well-trained specialist who uses the endoscope to diagnose, and in some cases treat, problems of the upper digestive system. Your doctor will be assisted by specially trained nurses and technicians who are essential in performing the procedure safely and effectively.

If an ulcer is found, your doctor will then test you for the bacteria Helicobacter pylori (H. pylori). This test is important because treatment for an ulcer caused by H. pylori is different from that of an ulcer caused by nonsteroidal anti-inflammatory drugs (NSAIDs). H. pylori is most commonly diagnosed through blood test, although breath, stool and tissue tests also may be used.

UCSF Health medical specialists have reviewed this information. It is for educational purposes only and is not intended to replace the advice of your doctor or other health care provider. We encourage you to discuss any questions or concerns you may have with your provider.