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PH Test


Updated February 04, 2008

Photo by A.D.A.M.

Esophageal pH Monitoring

The pH procedure is done with a thin, plastic tube with a sensor that measures the amount of acid backing up into the esophagus. This procedure is often done when GERD symptoms are present but an endoscope exam doesn't detect any evidence of reflux disease.

The pH test measures how often and for how long stomach acid enters the esophagus, and how well it clears the esophagus.

What can be expected if the doctor orders pH monitoring?

  • The doctor inserts a tubular probe through the nose and into the esophagus. The tube stops just above the lower esophageal sphincter (LES). This can also be performed during endoscopy by clipping a pH monitoring device to the lining of the esophagus.

  • The tube is left in place for 24 hours. The patient is encouraged to engage in normal activities.

  • The patient keeps a record of any symptoms that are suspected to be acid reflux. The patient also will record other symptoms, such as coughing and wheezing. This can help the doctor determine if acid reflux is related to unexplained asthmatic or other respiratory symptoms.


Other diagnostic tests:


"Heartburn Or Gastroesophageal Reflux Disease (GERD)." The American College of Gastroenterology. 1 Feb 2007 <http://www.acg.gi.org/patients/women/whatisgerd.asp#4>.

"Heartburn? Could It Be GERD? Understanding Heartburn and Gastroesophageal Reflux Disease (GERD)." AN417/AGA/GERD/Booklet 12/3/03. American Gastroenterological Association. 1 Feb 2007 <http://www.gastro.org/user-assets/Documents/GERDBooklet.pdf>.

Related Video
Heartburn and Acid Reflux Testing - Endoscopy
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