Esophageal pH Test

An esophageal pH test measures and records the pH in your esophagus to determine if you have gastroesophageal reflux disease (GERD). The test can also be done to determine the effectiveness of medications or surgical treatment for GERD.

How an Esophageal pH Test Is Performed

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Use our online referral form or call
602-943-1111 to request a referral to a John C. Lincoln physician who specializes in esophageal pH tests.

  • A small capsule, about the size of a gel capsule, is temporarily attached to the wall of the esophagus during an upper endoscopy. The capsule measures pH levels in the esophagus and transmits readings by radio telecommunications to a receiver about the size of a pager. Worn on your belt or waistband, the receiver has several buttons on it. You'll press them to record gastroesophageal reflux disease (GERD) symptoms such as heartburn. The nurse will let you know which symptoms to record.
  • You'll be asked to maintain a diary to record certain events such as when you start and stop eating and drinking, when you lie down, and when you get back up. This will be explained by the nurse.
  • You'll return the receiver and diary when the monitoring period is over. The information on the receiver and diary will be downloaded to a computer and the results analyzed. Preliminary study data will be reviewed with you if you like.

After Completion of the Esophageal pH Test

  • Resume your normal diet and medications.
  • Your doctor will discuss the results of your test with you during your next scheduled appointment.
  • Normal activities — such as swallowing, eating and drinking — will cause the disposable pH capsule to detach and pass through the digestive tract in seven to 10 days on average.

No magnetic resonance imaging (MRI) tests should be performed for 30 days following capsule insertion.