Esophageal pH Monitoring

Your doctor has requested an esophageal (ee-SOF-uh-JEE-al) pH monitoring test for you. The symbol pH refers to acidity. This test is done to determine whether any pain or irritation you are experiencing may be caused by stomach acids flowing up into your esophagus (food pipe).

To conduct this test, your doctor will place a small plastic tube through your nose and into your esophagus. (Please refer to the illustration below.) You will be asked to wear a monitoring pack on a belt. The belt can be worn either around your waist or like a purse — over your shoulder and draped across your chest. During the test you should go about your regular activities: Try, as much as possible, to stick to your normal routine, including a regular diet, work, recreation, rest, and sleep. The monitoring period lasts 24 hours. After this time, you will return to the hospital to have the tube removed and to return the monitoring pack.


You should not eat breakfast on the morning of the test. Women should wear a blouse or dress that buttons up the front. Do not wear a full slip or camisole. Men should wear a shirt that buttons up the front. Do not wear a polo shirt or undershirt.


The nurse will insert a thin wire recording device, called an esophageal probe, into your nose and down your esophagus. You may experience discomfort in your nose and in the back of your throat when the probe is inserted. A few patients also may experience nausea or vomiting. Once the probe is inserted, it will not interfere with your breathing, talking, or eating. You will be able to blow your nose and cough. The end of the probe will be taped to your cheek to help hold it in place.

You will be given a monitoring pack on a belt to wear around your waist or draped across your chest. The monitoring pack weighs about 1 pound. As part of the test, a small plastic patch (electrode) will be taped on your skin in the area over your esophagus. A cable will be connected from this patch to the monitoring pack. Men may need to have a 3-inch area of their chest shaved where the patch will be applied.

Instructions for Monitoring and Recording Events

The monitoring pack you are carrying will store your esophageal pH values for the next 24 hours. You will be asked to write down events and activities in a diary you will be given. To make sure test results are accurate, please follow these instructions: Press the event pads on the monitor when an “event,” or symptom, occurs. Using a 24-hour clock (i.e., 1 p.m. would be 1300; 2 p.m. would be 1400, etc.), record your symptoms (i.e., chest pain, heartburn, nausea, tightness, squeezing sensation, “gas,” cough, vomiting, reflux, etc.) and activities in your diary, noting the specific time for each event. Also note times of meals and snacks along with a description of what you ate. Write down all alcoholic and nonalcoholic beverages you have. Record any medications you took and the times you took them. If you smoke, record each time you do so.

Your diary should look something like this, using the 24-hour clock:


Start Stop Activity or symptom
1000 Woke up
1020 Took blood pressure pills
1020 12 noon Grocery shopping
12 noon 1310 Lunch (spaghetti with sauce, bread, tea)
1330 1345 Argument with neighbor
1530 1533 Chest pain
1534  1700 Watched TV
1700  1800 Ate dinner (chicken, french fries, peas, applesauce, water)
1800 1830 Took walk
1830 2130 Read book
2130 2145 Felt nauseous
2200 Went to bed
210 Woke up. Went to bathroom, then back to bed
700 Woke up
730 750 Ate breakfast (cereal with milk)

Restricted Activities

Although you should try as much as possible to keep to your normal routine during the monitoring period, there are some things you should not do. Do not take a bath, shower, or swim while wearing the monitoring pack. Do not take the pack through an airport metal detector or have an x-ray taken while it is on. Do not stand closer than 3 feet from a microwave oven that is in use. Do not remove the recorder from its case or fasten the monitor to your belt; use the belt provided to fasten the monitoring pack.

In addition, be careful not to remove the tape used to fasten the probe to your cheek.

Dietary Restrictions

Do not eat or drink any of the following during the monitoring period:

  • Citrus fruits
  • Grapefruit juice and other fruit juices
  • Lemonade

Other than these foods, you should eat your regular diet. Remember to record everything you put into your mouth, including water. No chewing gum, no hard candies and no sipping on drink throughout the day.


Smoking is allowed during esophageal pH monitoring. However, you should note in your diary every time you smoke a cigarette, cigar, or pipe, or chew tobacco.

Changing Clothes While Wearing the Monitor

Do not disconnect the cable from the monitor pack.


If your doctor has prescribed medications, continue to take them during the test. Do not take Tagamet®, Zantac®, Pepcid®, Axid®, Prilosec®, or antacids, unless your doctor tells you to. Note in your diary what medications you took and at what times.


Because you may experience discomfort while wearing the probe, you should use your own judgment about whether you can drive safely. If you have any doubts, have someone else drive you while you are wearing the probe.


You do not need to wear the monitor belt and monitor while you are sleeping. Before you go to bed, unfasten the monitor belt and place it and the monitor on the bed by your pillow. . Pin the monitor to the bottom (fitted) sheet on your bed with large safety pins. This will allow you to turn comfortably during the night. In the morning, put the belt and monitor on again.


Use a washcloth to wash yourself. Do not take a shower or bath. Do not remove the tape from your cheek . Be careful not to wash near the tape on your cheek.

Emergencies, Problems, or Questions

Call your nurse or doctor before removing the probe in the event of an emergency; a health care worker should remove the probe for you in an emergency, if possible. If you must remove the esophageal probe, pull it slowly out of your nose. The probe is connected to a monitor pack like a phone jack; disconnect and throw away.

Contact your nurse to discuss any problems or questions.

My nurse is


My nurse’s telephone number is


Revised July 2013

UPMC | Affiliated with the University of Pittsburgh Schools of the Health Sciences | Supplemental content provided by Healthwise, Incorporated. To learn more, visit

For help in finding a doctor or health service that suits your needs, call the UPMC Referral Service at 412-647-UPMC (8762) or 1-800-533-UPMC (8762). Select option 1.

UPMC is an equal opportunity employer. UPMC policy prohibits discrimination or harassment on the basis of race, color, religion, ancestry, national origin, age, sex, genetics, sexual orientation, gender identity, marital status, familial status, disability, veteran status, or any other legally protected group status. Further, UPMC will continue to support and promote equal employment opportunity, human dignity, and racial, ethnic, and cultural diversity. This policy applies to admissions, employment, and access to and treatment in UPMC programs and activities. This commitment is made by UPMC in accordance with federal, state, and/or local laws and regulations.

Medical information made available on is not intended to be used as a substitute for professional medical advice, diagnosis, or treatment. You should not rely entirely on this information for your health care needs. Ask your own doctor or health care provider any specific medical questions that you have. Further, is not a tool to be used in the case of an emergency. If an emergency arises, you should seek appropriate emergency medical services.

Pittsburgh, PA, USA |