By Dr. Brian McDonough, Medical Editor

PHILADELPHIA (CBS) – There are certain procedures in medicine that have become more and more commonplace over time. An example is the endoscopy. It is used for many reasons but it is often recommended if you have moderate to severe acid reflux. During the test, your doctor will place a small tube, called an endoscope, down your throat.

One of the most interesting uses of an endoscopy is wireless esophageal ph monitoring. This test is another way to measure how much acid is in your esophagus.

During the endoscopy, a small capsule is placed on the wall of your esophagus. This capsule records the ph levels in your esophagus and sends the information to a small receiver you wear on a belt. When you have symptoms of gerd, you press a small button on the receiver. Your doctor may also ask you to record some of your daily activities, such as when you eat and drink, lie down, and get up.

In most cases, you will wear the monitor for about 48 hours. The capsule will detach on its own and pass through your digestive system.