What Is a 24-Hour pH Probe Study?
A 24-hour pH probe study is a test used to measure the amount of acid refluxing from the stomach into the esophagus over a full day. It is the most accurate way to diagnose gastroesophageal reflux disease (GERD) and is often ordered when symptoms such as heartburn, chest pain, chronic cough, or throat clearing are not fully explained by other tests, or when your provider needs data before recommending medication or surgery.
How the Test Works
A thin, flexible catheter (pH catheter) is gently passed through one nostril and positioned in the lower esophagus. The catheter is connected to a small recording device — about the size of a cell phone — that you wear on a strap around your neck or waist for the full 24 hours. The device continuously records the acidity level in your esophagus throughout the day and night.
Medications to STOP Before the Test
Certain medications suppress acid and will interfere with test results. Stop them as follows unless your provider specifically instructs otherwise:
- Proton pump inhibitors (PPIs) — Stop 7 days before: Prilosec (omeprazole), Nexium (esomeprazole), Prevacid (lansoprazole), Protonix (pantoprazole), Dexilant, Aciphex
- H2 blockers — Stop 2 days before: Pepcid (famotidine), Zantac (ranitidine), Tagamet (cimetidine)
- Antacids — Stop 1 day before: Tums, Rolaids, Maalox, Mylanta, Gaviscon
Do not stop any medications without confirming with our office first, especially if you take them for conditions other than reflux.
Before Your Appointment
- Do not eat or drink anything for 6 hours before your scheduled appointment time
- Wear comfortable clothing with a waistband or strap suitable for holding the recording device
- Arrange for someone to drive you home if needed (most patients drive themselves)
During the 24-Hour Study
- Eat your normal diet — do not change what you eat; the goal is to capture your typical reflux pattern
- Continue your normal daily activities — go to work, exercise lightly, and sleep as you normally would
- Press the event button on the recorder any time you experience a symptom (heartburn, chest pain, coughing, throat clearing, burping)
- Keep the diary provided: record the times you eat meals and snacks, the time you lie down to sleep, and the time you wake up
- Do not submerge the recording device in water — no baths, pools, or swimming. Brief showers are acceptable if the device is kept dry
Returning the Equipment
Return to our office the following day at your scheduled appointment time. The catheter will be removed — this takes only a few seconds and is not painful. The data from the recorder will be downloaded and analyzed by your provider, who will discuss the results with you at a follow-up appointment.
Questions?
Contact Sleep and Sinus Centers if you have questions about your medications, if the catheter causes significant discomfort during the study, or if you experience nosebleeds or swallowing difficulty after placement.
Don’t let allergies slow you down. Schedule a comprehensive ENT and allergy evaluation at Sleep and Sinus Centers of Georgia. We’re here to find your triggers and guide you toward lasting relief.