The stomach acid test is used to measure the amount of acid in the stomach. It also measures the level of acidity in stomach contents.
Gastric acid secretion test
How the test is performed
The test is done after a period of not eating so that fluid is all that remains in the stomach. Stomach fluid is removed through a tube that is inserted into the stomach through the esophagus (food pipe).
To test the ability of the cells in the stomach to release acid, a hormone called gastrin may be injected into your body. The stomach contents are then removed and analyzed.
How to prepare for the test
You will be asked not to eat or drink for 4 - 6 hours before the test.
How the test will feel
You may have some discomfort or a gagging feeling as the tube is passed through your nose or mouth, and down your esophagus.
Why the test is performed
Your doctor may recommend this test for the following reasons:
To check if anti-ulcer medications are working
To check if material is coming back up from the small intestine
The presence of bile in the stomach indicates material is backing up from the small intestine ( duodenum). This may be normal. It may also happen after part of the stomach is removed with surgery.
What the risks are
There is a slight risk of the tube being placed through the windpipe and into the lungs instead of through the esophagus and into the stomach.
Scubert ML, Kaunitz JD. Gastric secretion. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2010:chap 49.
George F. Longstreth, MD, Department of Gastroenterology, Kaiser Permanente Medical Care Program, San Diego, California. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, David R. Eltz, and Stephanie Slon.