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The Esophagus and pH Testing

The 24-hour esophageal pH test is an outpatient procedure performed to measure the pH or amount of acid that flows into the esophagus from the stomach during a 24-hour period.

The pH test is commonly used to help identify the cause of various symptoms, including:

Recommended Related to Digestive Disorders

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  • Heartburn, primarily in patients who have failed medical treatment and are candidates for surgery
  • Uncommon symptoms of GERD (gastroesophageal reflux disease), such as chest pain, chronic cough, and asthma


How Is the Esophageal pH Test Performed?

The equipment used in the esophageal pH test consists of a small probe that is inserted through your nostril and positioned near the lower esophagus. The probe is plugged into a small unit (or monitor) worn on your belt or over your shoulder.

The device has several buttons that, when pressed, record:

  • The occurrence of symptoms
  • When you eat and lie down

A nurse will review the monitoring instructions with you.

Be careful with the monitor and keep it dry at all times.

How Should I Prepare for the Esophageal pH Test?

When preparing for the esophageal pH test, do not eat or drink for 4 to 6 hours before your doctor's appointment.

Tell your doctor if you are pregnant, have a lung or heart condition or any other diseases, or are allergic to any medications.

Can I Continue to Take Medication Before the pH Test?

There are several medications that may affect the results of an esophageal pH test. These include:

There are other medications that may affect the test results. Talk to your doctor about all medications you are taking before undergoing the procedure.

Do not discontinue any medication without first consulting with your primary or referring doctor. If proton pump inhibitors need to be discontinued, you may need to take a week off these medications before doing the test.

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