Houston Methodist. Leading Medicine.
Houston Methodist. Leading Medicine

48-Hour pH Bravo Capsule

Testing Information: 48-Hour pH Bravo Capsule

What is a 48-Hour pH Bravo Capsule Test?

The 48-hour pH Bravo Capsule test is done to evaluate 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.


1. Some patients may experience some chest discomfort.

2. The 48-Hour Bravo pH Capsule is not for everyone. The patient should be instructed by their physician to discontinue anticoagulants (blood thinners) one week prior to 48-Hour pH Bravo Capsule.  Talk with your physician regarding testing options.

3. Patients with a pacemaker or implantable cardiac defibrillator should not undergo a Bravo pH test.

4. The Bravo pH capsule contains a small magnet and you should not have an MRI for 30 days after the Bravo pH test.

Before the procedure

Follow your physician’s instructions regarding discontinuing medications. 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 7 days prior to the test. Your physician will instruct you whether to take these medications or withhold them.

If your physician has instructed you to withhold the above medications and you are experiencing discomfort you may take antacids such as, Rolaids®, Tums® or Mylanta®.

What to do the night before the procedure

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.

Preparing for the procedure

The patient is admitted to the Reflux Center as an outpatient. Vital signs are taken.

During the procedure

  1. The capsule, approximately the size of a gel cap is inserted directly into the mucosa above the gastro-esophageal junction via a specialized delivery system or during upper endoscopy.
  2. After the capsule is inserted, 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 recorder 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) when eating or laying down.

After the procedure

You may drive yourself home after the procedure. After the test is completed, the diary and Bravo Receiver is returned and the information is uploaded to a computer that will perform analysis for review. The capsule naturally falls off in 5-7 days on average and passes through the digestive tract and is eliminated from the body.

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 may minimize this sensation. Do not use throat lozenges since they may change the results of the test.