On this page
At a glance
- A small capsule is attached to the lining of the esophagus during an upper endoscopy.
- It records acid levels and sends them wirelessly to a small receiver you carry.
- Longer (96-hour) recordings are preferred when available, because reflux varies from day to day.
- The capsule detaches on its own within days and passes through the digestive tract.
What the test measures
The main result is acid exposure time — the percentage of the recording during which the esophagus is acidic. The test also counts reflux events and checks whether the symptoms you record line up with them.
Under the Lyon consensus, acid exposure above 6% of the time (on at least two days of a multi-day wireless study) confirms GERD, and below 4% on every day argues strongly against it. Results between those values are considered borderline and interpreted alongside other findings. The AGA recommends prolonged wireless monitoring — ideally 96 hours — when GERD hasn’t been proven, because a single day can miss or overstate the problem.
How it is placed
The capsule, about the size of a gel cap, is attached to the lining of the lower esophagus during an upper endoscopy, usually with sedation. It sits a few centimeters above the valve, where it samples acid levels continuously.
During the recording
You carry a small receiver and go about your usual routine — including meals that tend to cause symptoms, since the goal is to capture a typical day. You’ll press buttons or keep a diary to mark:
- Symptoms such as heartburn, regurgitation, chest discomfort, or cough
- Meals
- When you lie down and get up
Some people feel the capsule, especially when swallowing, as a mild foreign-body sensation. Chewing well and taking sips of liquid with food usually helps. If swallowing becomes painful or chest pain develops, contact the team that placed it.
After the test
The capsule detaches from the lining on its own, usually within days, and passes naturally. You return the receiver so the data can be analyzed. Because the capsule is a small electronic device, you should avoid MRI until it has passed — your testing team will tell you how long to wait and when a confirming X-ray might be needed.
Tell the team before the test if you have a pacemaker or implanted defibrillator, a bleeding disorder or take blood thinners, or known narrowing of the esophagus.
Preparing — medications
When the purpose is to find out whether you have GERD, the test is most informative off PPIs; the AGA suggests holding them for 2 to 4 weeks when possible. Your testing team will give you specific instructions, which may differ depending on the question being asked.
Common questions
What is a Bravo test like?
The capsule is placed during an endoscopy, usually under sedation; afterward most people feel little or a mild sensation when swallowing, and go about their normal routine while it records.
Because it is placed during an upper endoscopy, you’ll need a driver that day. Once you’re home, you carry a small receiver and eat, work, and sleep as usual, pressing buttons to mark symptoms, meals, and when you lie down.
Some people notice the capsule when they swallow, a little like a pill that hasn’t fully gone down. Chewing food thoroughly and drinking with meals helps. If swallowing becomes painful, or you develop chest pain, contact the team that placed it. The capsule falls off on its own and passes without you noticing.
Sources
- Yadlapati R, et al. AGA Clinical Practice Update on the Personalized Approach to the Evaluation and Management of GERD. Clin Gastroenterol Hepatol. 2022;20(5):984–994.
- Gyawali CP, et al. Updates to the modern diagnosis of GERD — Lyon consensus 2.0. Gut. 2024;73(2):361–371.
- Katz PO, et al. ACG Clinical Guideline for the Diagnosis and Management of GERD. Am J Gastroenterol. 2022;117(1):27–56.
This page is general education. It can’t account for your history, test results, or other conditions, so please discuss your situation with your own clinician.