Ulica kneza Branimira 71, Zagreb
Book an appointment +38512310067

24-hour pH monitoring (esophageal pH test)


24-hour esophageal pH monitoring measures and records the pH in the esophagus with the aim of establishing gastro-esophageal reflux disease (GERD).  Esophageal reflux is a condition in which stomach acid refluxes or moves back into the esophagus. When reflux occurs frequently and to a greater extent than expected, it can cause various gastrointestinal and respiratory symptoms. The esophageal pH test measures how often the stomach contents reflux into the lower esophagus and how much acid the reflux contains.   

The examination is performed with the child sitting, whereby a thin, small tube with a device on the tip that senses acid is gently passed through the nose, down the esophagus, and positioned about 3 to 5 centimeters above the stomach. The tube is fastened to the side of the face with clear tape. The end of the tube that comes out of the nose is attached to a portable recorder that is worn over the shoulder. The recorder has several buttons on it that you will press to mark certain events. A nurse will review the monitoring instructions with you.


  1. It is important to explain to your child how the procedure is to be performed.
  1. Seven days before the monitoring period, the child should not take proton pump inhibitors Controloc® (pantoprazole), Nexium® (esomeprazole)
  2. Two days (48 hours) before the monitoring period, the child should not take H2 blockers: Zantac®, Ranix®, Peptoran ® (ranitidine),
  3. Six hours before the monitoring period, the child should not take antacids, Rennie® or alginates, Gaviscon®, Reflustat®
  4. Four to six hours before your appointment, the child should not eat or drink.

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

When coming for 24-hour pH monitoring, please follow these instructions:

  1. Come on time; you will spend around 1 hour in our clinic
  2. Please inform us at least 24h in advance if you need to cancel. 24-hour pH-monitoring is not recommended if the child is acutely ill, has a clogged nose or is on antibiotics or other treatment that may affect the test.
  3. Bring complete medical documentation