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 (GERD) GERD (acid reflux) is a disease caused by your stomach contents and stomach acid flowing back up your esophagus. Your esophagus is the tube that connects your throat to your stomach. Acid reflux... read more (gastroesophageal reflux disease).
The Esophagus
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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