Esophageal pH Monitoring (24 Hour)

What is 24 hour pH/impedance monitoring test?

This test enables you doctor to determine the number of episodes of gastroesophageal reflux, which means the backward flow of the stomach’s contents into the esophagus.  It can determines how long each of these episodes last and what the acid measurement is. The impedance part of the test measures the volume of gastroesophageal reflux.   Understanding this is important in recommending the correct treatment for you.

Why is 24 hour pH/impedance recommended?

pH monitoring can be helpful to evaluate chest pain, reflux, heartburn, respiratory symptoms, voice hoarseness or vomiting.


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If you have diabetes, ask your regular doctor for diet and medication restrictions. Do not take your oral diabetes medicine on the day of your procedure. If you take metformin, stop taking it the day before your colonoscopy. Also, please bring your Insulin and Insulin syringes with you to your procedure; we will check your blood sugar before and after the procedure.

If you take a medication to thin your blood (such as Coumadin, Plavix, Pradaxia or Lovenox) be sure to call 404-605-3840.

If you are or may be pregnant, please discuss the risks and benefits of this procedure with your doctor.

If you must cancel or reschedule your appointment, please call 404-355-3200 at least three days prior to your procedure to avoid a late cancellation fee of $150.00.

If you have any special needs, please notify the admitting nurse prior to your procedure (i.e. a pacemaker, internal defibrillator, latex allergy, need an interpreter, or are allergic to eggs, nuts, or soy).

If you currently are taking other prescription medications, you may continue to take all other medications as instructed by the prescribing physician. However, your doctor may want to do this study off of the following medications for 10 days: Aciphex® (rabeprazole), Nexium® (esomeprazole), Prevacid® (lansoprazole), Dexilant® (dexlansoprazole), Prilosec® (omeprazole), Protonix® (pantoprazole) or Zegerid® (omeprazole/ sodium bicarbonate). The following medications may not be taken for two days: Pepcid® (famotidine), Tagament® (cimetidine), Zantac® (ranitidine), Axid® (nizatidine).   Your doctor will let you know prior to the test if you should stop your medications or continue your medications.


To ensure a successful exam, please follow all instructions carefully. Failure to accurately and completely prepare for your exam may result in the need for an additional procedure and both procedures will be billed to your insurance.

The night before your exam:

  • Stop eating solid foods at midnight.
  • Clear liquids are okay to drink (examples: water, Gatorade, clear broth, black coffee and apple juice).
  • Do not drink red liquids or alcoholic beverages.

The day of your exam:

  • You may take your usual medications (exceptions noted above) with up to 4 oz. of water at least 2.5 hours prior to your procedure. Be sure to wear comfortable clothes and shoes that will remain on your feet (preferably tennis shoes) to your procedure. Please do NOT wear flip flops, sandals, or backless shoes.
  • Please remove ALL jewelry including earrings, rings, bracelets, anklets, necklaces, and watches prior to the procedure, and be sure to leave any and all valuables at home.
  • A staff member designated by the physician will place the tube.  A very thin tube will be passed through your nose into your esophagus.  The tube will be secured to your nose with tape.  The external end will be attached to a small recorder.  You can wear the recording device on a belt around your waist or carry it like a shoulder strap.  For 24 hours (your testing time), you will be asked to keep a diary of when you eat, sleep, and any symptoms that you experience.  These symptoms (example: coughing or heartburn) will then be correlated with the information from the tube in your esophagus.
  • Plan to spend up to two hours at the endoscopy center the day of your procedure. The exam itself takes about 15 minutes to complete.
  • Please do not take any over the counter antacids during the study period, such as Tums® , Rolaids®, Maalox®, Mylanta®, Gaviscon or Carafate® (sucralfate).
  • You will return to the hospital and the tube will be removed the next day. A computer will analyze the information from your recording device and your diary.  The results will be given to a doctor who will study the combined data and send a report to your primary physician.

Are there any complications?

This test is very safe with very few potential serious complications.  You may feel minor discomfort while the tube is in place and it is normal to feel some “tugging” while eating.

Please call 404-605-3840 if you have any questions regarding the actual procedure.

Additional information:

The Piedmont Hospital GI lab is located on the first floor of the 77 building. It is most convenient to park in the North parking deck. Take the elevator to the bridge level (BR). You will need to go to the 77 building registration office to register for your procedure. After getting off at the bridge level you will walk through a glassed-in bridge and go straight. You will pass the 77 building (D) elevator, which will be located on your left. The registration office is located in the next hallway on your left. Once inside, a member of the registration staff will help you complete some additional paperwork, and then escort you to the GI Lab for your procedure. This should take approximately 15 minutes.

Please be certain to have all of the following items with you:

  • A list of all your current prescription medication and all your over the counter medications.
  • A photo ID.
  • Co-pays are required on the day of your appointment. If you have any questions about pre-certification, please call our business office at 404-603-3543.