48-Hour pH Bravo Capsule

The 48-hour Bravo pH capsule test evaluates the extent of acid reflux, or backflow, from the stomach into the esophagus. This may be done during an upper endoscopy or through the mouth using a specialized delivery system. Exactly where the capsule is placed is determined via endoscopy or manometric testing of the esophagus.
The 48-hour Bravo pH capsule test is not for everyone and the following list outlines risks and other considerations:

  • Some patients may experience mild chest discomfort.
  • Consult your physician for testing options and instructions about discontinuing anticoagulants (blood thinners) one week prior to the test.
  • Patients with a pacemaker or implantable cardiac defibrillator should not undergo a Bravo pH capsule test.
  • The Bravo pH capsule contains a small magnet and you should not have an MRI for 30 days after the Bravo pH capsule test. 

About the 48-Hour Bravo pH Capsule Procedure

You will be admitted as an outpatient where staff will take your vital signs. The following steps will occur during the procedure:

1. The Bravo capsule, approximately the size of a gel capsule, is inserted directly into the mucosa above the gastroesophageal junction via a specialized delivery system or during an upper endoscopy.

2. After inserting the capsule, the delivery system is released and removed, leaving the capsule in place. The capsule contains a measuring device that regularly transmits pH readings via telemetry to a recording device (the size of a pager) worn on the patient’s belt.

3. A diary is given to you to document the times when you have reflux symptoms (coughing, heartburn, regurgitation) while eating or lying down.
While the Bravo capsule is in place, some patients experience a vague sensation that something is in their esophagus and feel the capsule when they eat or when food passes by the capsule. Should you experience this, chewing food carefully and drinking fluids should help minimize this sensation. Do not use throat lozenges, which may change the results of the test.

Follow your physician’s instructions regarding discontinuing medications prior to the procedure. Drugs such as proton pump inhibitors (AcipHex®, Prilosec®, Prevacid®, Protonix®, Nexium®, Zegerid®, Dexilant®) or H2 blockers (Axid®, Pepcid®, Tagamet®, Zantac®) may affect test results. It is recommended that these drugs be withheld seven days prior to the test. If your physician has instructed you to withhold these medications, and you are experiencing discomfort, you may take antacids, such as Rolaids®, Tums® or Mylanta®. 

Do not eat or drink anything after midnight prior to your test. Do not smoke the day of your test. If you are an asthma patient, bring your inhaler.
You may drive yourself home after the procedure. Once the test is completed, you will return the diary and Bravo receiver and our staff will upload the information to a computer for analysis. The capsule naturally falls off in five to seven days on average, passing through the digestive tract and eliminated from the body.


Houston Methodist provides diagnostic testing, including the 48-hour Bravo pH capsule procedure, at the following convenient locations.