The test is done in a gastroenterology laboratory. A nasogastric (NG) tube will be inserted through one side of your nose and down into your esophagus. Mild hydrochloric acid will be sent down the tube, followed by salt water (saline) solution. This process may be repeated several times.
You will be asked to tell the health care team about any pain or discomfort you have during the test.
How to prepare for the test
You should not eat or drink anything for 8 hours before the test.
How the test will feel
You may have a gagging feeling and some discomfort when the tube is put into place. The acid may cause symptoms of heartburn. Your throat may be sore after the test.
Why the test is performed
The test attempts to reproduce symptoms of gastroesophageal reflux (stomach acids coming back up into the esophagus).
The test results will be negative.
What abnormal results mean
A positive test suggests that the symptoms are caused by esophageal reflux of acid from the stomach.
What the risks are
There is a risk of gagging or vomiting.
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Kahrilas PJ, Pandolfino JE. Esophageal neuromuscular function and motility disorders. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2010:chap 42.
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and George F. Longstreth, MD, Department of Gastroenterology, Kaiser Permanente Medical Care Program, San Diego, California. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.