GastroenterologyGastroenterology

pH Monitoring

Normal Range
DeMeester Score < 14.72
Sample Type
Esophageal Fluid (In-vivo)
Fasting
Required
Unit
pH Units

Function

Ambulatory pH monitoring is the gold standard for diagnosing Gastroesophageal Reflux Disease (GERD). It measures the frequency and duration of stomach acid backing up into the esophagus over a 24 to 48-hour period. This is typically done using a thin catheter passed through the nose or a wireless capsule (Bravo) attached to the esophageal wall.

Why it is Ordered

It is ordered when symptoms like heartburn, regurgitation, or chronic cough do not respond to Proton Pump Inhibitors (PPIs) or when a physician needs to confirm GERD before surgical intervention (like Nissen Fundoplication). It helps distinguish between true acid reflux, hypersensitive esophagus, and functional heartburn.

Associated Conditions

  • GERD: Chronic acid exposure causing tissue damage.
  • Laryngopharyngeal Reflux (LPR): Acid reaching the throat and larynx.
  • Barrett’s Esophagus: Pre-cancerous changes due to chronic acid exposure.
  • Non-Cardiac Chest Pain: Ruling out reflux as a cause for chest pain symptoms.

Check Your Result

Check Your Result

Interactive
pH Units

Enter your lab result to see where you stand compared to the standard reference range.

Why Context Matters

Results depend heavily on the patient following a 'normal' diet during the test; if a patient avoids trigger foods out of fear during the monitoring period, the test may yield a false negative. Furthermore, displacement of the pH probe or recent use of acid-suppressing medications (if not instructed to stop) can invalidate the DeMeester score.

Lab ranges are statistical averages, not biological laws. "Normal" for a 20-year-old male isn't normal for a 60-year-old female.

Clinical References

Source-of-truth databases and clinical guidelines for pH Monitoring:

Research & Guidelines

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DR

Medically Reviewed by Dr. Binoy Babu, MBBS

Board Certified Doctor • 10+ Years Clinical Experience

Dr. Babu is a practicing physician dedicated to empowering patients with clear, actionable medical information. He founded 2opi to bridge the gap between complex lab reports and patient understanding, ensuring everyone has access to a reliable second opinion.

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