Esophagus: 48-Hour Bravo Esophageal pH Test

The Bravo pH test for stomach acid involves attaching a capsule to your esophagus to measure acid reflux from your stomach. Knowing if and when stomach acid backs up into your esophagus can help your provider treat your symptoms. These might include heartburn and sore throat.


Esophageal PH Test

What is a Bravo™ pH monitoring test, and why do I need to have it?

The BravoTM pH test measures the pH level of your esophagus. The pH level of a substance tells whether something is basic or acidic. Sometimes, stomach acid backs up into the esophagus (the tube that connects the throat to the stomach, or the “food pipe”) which can increase the acidity level within your esophagus.

Stomach acid isn’t the only thing that can back up into the esophagus. Food particles and other digestive juices can also splash back. When reflux occurs on a regular basis, it can cause permanent damage to the esophagus. The Bravo pH test reveals how often stomach contents reflux into the lower esophagus and how much acid the reflux contains.

If your healthcare provider thinks you might have gastroesophageal reflux disease (GERD), they might ask you to have a Bravo pH test. People who are diagnosed with GERD often experience:

  • Heartburn.
  • Chest pain.
  • Coughing.
  • Sore throat or hoarse voice.


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Test Details

How does a Bravo pH test work?

The Bravo pH monitoring test is a system that includes:

  • A pH-sensing wireless capsule that is placed into esophageal tissue to measure pH levels.
  • A recorder you wear to capture the data from the capsule
  • A software system that makes it all work.

A small capsule, about the size of a gel cap, is temporarily attached to the wall of the esophagus during an upper endoscopy. The capsule measures pH levels in the esophagus and transmits readings to a receiver (about the size of a pager) worn on your belt or waistband.

The receiver has several buttons on it that you will press to record symptoms of GERD such as heartburn (a caregiver will tell you what symptoms to record). You will be asked to maintain a diary to keep track of events like when you start and stop eating and drinking, when you lie down and when you get back up. This will be explained by your caregiver.

Who performs a Bravo pH monitoring test?

The capsule will be placed by a digestive disease provider skilled in gastrointestinal endoscopy. The upper endoscopy process uses thin tubing with cameras to look into your gastrointestinal system through your esophagus and down toward your stomach. The process can be used both to examine your system and to treat certain conditions.


How do you prepare for the Bravo pH test?

Let your doctor know if you have a pacemaker or implantable heart defibrillator, a history of bleeding problems, dilated blood vessels, and any other previously known problems with your esophagus.

  • Seven days before the monitoring period, don’t take proton pump inhibitors such as omeprazole (Prilosec®), lansoprazole (Prevacid®), rabeprazole (Aciphex®), pantoprazole (Protonix®), esomeprazole (Nexium®).
  • Two days (48 hours) before the monitoring period, don’t take the H2 blockers ranitidine (Zantac®), cimetidine (Tagamet®), famotidine (Pepcid®), nizatidine (Axid®); or the promotility drug, metoclopramide (Reglan®).
  • Six hours before the monitoring period, don’t take antacids (such as Alka-Seltzer®, Gaviscon®, Maalox®, Milk of Magnesia®, Mylanta®, Phillips®, Riopan®, Tums® or any other brands).
  • Four to six hours before your appointment, don’t eat or drink.

Please note: Occasionally, your doctor may want you to continue taking a certain medication during the monitoring period to determine if it is effective.

What happens on the day of the Bravo pH test?

You should wear comfortable clothing. You might be asked to change into a gown at the hospital or outpatient facility.

Leave your jewelry and credit cards at home. You won’t be able to wear your glasses or dentures during the procedure.

You should have a responsible person to drive you home.

Your healthcare provider will again explain the procedure and what to expect. This procedure is done under twilight sleep. They will tell you about possible complications or side effects.

Your provider will apply a local anesthetic (pain-relieving medication) at the back of your throat.

The provider will insert an endoscope into your mouth and into your esophagus (the "food pipe" leading from your mouth into your stomach). The endoscope does not interfere with your breathing.

The provider will attach the capsule to tissue on your esophagus and make sure that the capsule is sending signals to the recorder.

The procedure lasts only a few minutes.


Does the Bravo pH monitoring test hurt?

You’re probably wondering what your Bravo test experience will be like. Your throat might be a little sore. You might feel like something is in your throat. If you have any symptom that is extreme or that concerns you, contact your healthcare provider.

What happens during the Bravo pH monitoring test after the capsule is placed?

Here’s what you need to know about what happens during the study.

  • Activity: Follow your usual daily routine. Don’t reduce or change your activities during the monitoring period. If you change things, the monitoring results aren’t as useful. Note: Don’t get the receiver wet because it’s not waterproof.
  • Eating: Eat your regular meals at the usual times. If you don’t eat during the monitoring period, your stomach won’t produce acid as usual, and the test results won’t be accurate. Eat at least 2 meals a day. Eat foods that tend to increase your symptoms (without making yourself miserable). Avoid snacking. Don’t suck on hard candy or lozenges and don’t chew gum during the monitoring period.
  • Lying down: Remain upright throughout the day. Don’t lie down until you go to bed (unless napping or lying down during the day is part of your daily routine).
  • Medications: Continue to follow your doctor’s advice regarding medications to avoid during the monitoring period.
  • Recording symptoms: Press the appropriate button on the receiver when symptoms occur (as discussed with the nurse). Record the time you start and stop eating and drinking (anything other than plain water). Record the time you lie down (even if you’re just resting) and when you get back up. Someone on your healthcare team will explain all of this. .
  • Unusual symptoms or side effects: If you think you may be experiencing any unusual symptoms or side effects, call your doctor.

You’ll return the receiver and diary when the monitoring period is over. The information on the receiver and diary will be downloaded to a computer and the results will be analyzed.

What are the risks and benefits of the Bravo pH monitoring test?

Finding out if you have acid reflux is important. If you do have the more severe version (GERD), it could be causing damage to your esophagus, which could mean you could develop problems that are more serious. These include Barrett’s esophagus or esophageal cancer.

Finding out that you don’t have acid reflux is also important. Many people are taking medication like PPIs that aren’t working. You don’t need to take medication that is not indicated. If you don’t have acid reflux, your healthcare team can then help you find out what is really causing your symptoms.

Any procedure has risks, but the Bravo test has had few complications. These have included problems with the equipment that make the results unreliable. The capsule might fail to stay in place for the full testing period. Or, it might not detach when it’s supposed to do so.

Rarely, people having this test might feel some discomfort when they swallow, chest pain or back pain. You may have a sore throat from the endoscopy for a day or so.

There are other possible, though very unlikely, risks. These include damage to the tissue of your esophagus or intestines, possible bleeding or aspiration (breathing in) of the capsule.

Results and Follow-Up

What happens after the Bravo pH monitoring test?

After the study is complete, you:

  • Can resume your normal diet and medications.
  • Can resume your normal activities – such as swallowing, eating and drinking. This will cause the disposable pH capsule to detach and pass through the digestive tract in seven to 10 days on average.
  • Can’t have an MRI exam (magnetic resonance imaging) for 30 days after the capsule has been inserted.
  • Will meet with your healthcare provider to discuss the results of the monitoring test. Your provider will work with you to develop a plan to manage your symptoms.
Medically Reviewed

Last reviewed on 04/02/2021.

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