48-Hour Ambulatory pH Testing
This test is part of your diagnostic process to determine the extent of acid reflux, where stomach acids splash back into your esophagus. Acid reflux can lead to various symptoms, including heartburn, chest pain, abdominal discomfort, hoarseness, coughing, or asthma attacks.
During an endoscopy (EGD), a miniature pH capsule, about the size of a gel cap, will be placed beside your esophagus. Over the next 48 hours, you will carry a small recording device, which can be conveniently clipped to your waistband or belt. It’s crucial to maintain a detailed diary of your daily activities, meals, and symptoms. The accuracy of this diary is vital, as it forms the basis for an accurate diagnosis. A poorly documented diary can result in an inaccurate study.
After 48 hours, you will return the recording device and your diary to the clinic, either by mail or in person. Your doctor will then analyze the data from the recording device to determine how frequently stomach acid enters your esophagus and how this correlates with your daily activities and symptoms. Your diary plays a crucial role in this process, so please be as precise as possible.
Important Medication Instructions
Before the test begins, you must not eat or drink anything for at least 6 hours.
- Stop taking antacid medications such as Prilosec (Omeprazole), Prevacid (Lansoprazole), Aciphex (Rabeprazole), Protonix (Pantoprazole), Nexium (Esomeprazole), or Dexilant for 7 days before the test.
- Stop all other antacid medications such as Zantac, Tagamet, Axid, Carafate, or Pepcid for 3 days before the test.
- Stop medications such as Propulsid or Reglan for 3 days before the test.
- You may take liquid antacids such as Maalox or Mylanta up until midnight before the test.
- Do not take any of the above medications during the 48 hours that the Bravo capsule is recording.
- During the test, avoid continuous consumption of citrus and fruit beverages, as well as soft drinks, coffee, and tea, as these can affect the data. You may consume these beverages as part of your meals and snacks, but remember to record them in your diary.
- When recording the time for each event in your diary, use the time indicated on the digital screen of the recording device. Be sure to record the starting and ending times for all activities, especially for eating or sleeping. Detailed instructions on using the recorder will be provided after the capsule is placed.
After the Test
You can resume taking your acid reflux medications after the testing period is complete.
- The disposable pH capsule will dislodge from your esophagus and pass with a normal bowel movement, typically within a few days after the test.
- Since the capsule contains a very small magnet, it’s advisable to avoid having an MRI within 30 days of the pH test.
