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Acid-Related and Reflux-Related Tests

By

The Manual's Editorial Staff

Last full review/revision Jun 2020| Content last modified Jun 2020
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Your stomach makes acid to help you digest food.

Acid reflux is when stomach acid flows back up through your esophagus toward your throat. Your esophagus is the tube that connects your throat to your stomach. Acid reflux can cause a burning pain in your upper belly and chest. The pain is sometimes called heartburn.

Acid reflux is also called GERD (gastroesophageal reflux disease).

The Esophagus

The Esophagus

What are the tests for acid reflux?

Doctors put instruments in your esophagus to measure how much acid is in your esophagus. There are 2 types of tests:

  • Catheter-based monitoring, which uses a flexible tube (catheter) to measure the acid

  • Wireless monitoring, which uses a radio capsule to measure the acid

For either test, you can’t eat or drink anything after midnight before the test, but you can eat and drink as usual while the instruments are in your esophagus.

These tests are very safe.

Catheter-based monitoring

  • Your doctor puts a thin plastic tube (catheter) through your nose and throat and down into your esophagus

  • The tube has a probe that detects acid

  • The tube stays in your esophagus for 24 hours while you keep track of your symptoms, meals, and sleep in a diary

  • Wires inside the tube send information about acid in your esophagus to a recorder

  • Your doctor compares the information from the recorder with your diary to see if your symptoms happened while acid was in your esophagus

Some catheters can also measure other substances like mucus flowing up your esophagus.

Wireless monitoring

  • After giving you medicine to make you sleepy, your doctor passes a flexible viewing tube through your mouth to attach an acid-measuring capsule to the lower part of your esophagus

  • You keep track of your symptoms, meals, and sleep in a diary

  • The capsule measures acid in your esophagus and sends the information wirelessly to a receiver you wear

  • Your doctor compares the information with your diary to see if your symptoms happened while acid was in your esophagus

  • The capsule falls off within a week and passes through your intestines and out of your body in your stool

NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version
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