What is the Bravo pH monitoring system? The Bravo system is a pH test to help your doctor determine if you have acid reflux. A pH test measures the degree of acidity or alkalinity in your esophagus. The test period usually lasts 24 to 48 hours, and measures acidity in two ways: How often stomach acid flows into the lower esophagus Degree of acidity during the test period Information from the pH test helps your doctor diagnose GERD (gastroesophageal reflux disease) and plan your treatment. Bravo system consists of a capsule, approximately the size of a gel cap that is temporarily attached to the wall of your esophagus. The capsule measures pH levels in you esophagus and transmits this information wirelessly to a portable receiver you wear on your waistband. What should I expect during a Bravo test? You will sit or lie back while your doctor inserts the pH capsule into the esophagus. After the capsule is in place, suction is applied, drawing a small amount of tissue into the capsule. The capsule is locked in place with typically little or no discomfort. As soon as the capsule is attached, it begins measuring the pH levels in your esophagus. The capsule transmits these measurements wirelessly to a small receiver you wear on your waistband or belt. As long as the capsule and receiver are within 3 feet of each other, the system will measure and record your pH levels. This means you can place the receiver nearby when bathing or sleeping without interrupting the test.