24-Hour PH Probe Study A PH Probe is a 24-hour test that measures the frequency of stomach acid that backs up into the esophagus. It is the most effective method for diagnosing Gastroesophageal Reflux Disease (GERD).
A small flexible tube is passed through one nostril and positioned in the esophagus. The tubing is attached to a recorder and you may resume normal activities.
During this time, you will be asked to keep a diary of your food intake. After 24 hours you will be asked to return and have the tube removed and your physician will review the information.
