Esophagus tests measure muscle pressure and movement, coordination, and strength of the tube that connects the throat to the stomach (esophagus). It tests how well the ring of muscles (sphincters) at the top and bottom of the esophagus work. See a picture of the esophagus.

The most common esophagus tests include:

• pH monitoring (esophageal acidity test), which measures the acid content (pH) in the esophagus. A low pH for long periods indicates frequent abnormal backflow (reflux) of stomach acid into the esophagus (gastroesophageal reflux disease, or GERD).
• Esophageal manometry, which measures the strength and pattern of muscle contractions in the esophagus. This test can detect:
  • Weakness in the lower esophageal sphincter (LES), which allows acid to reflux into the esophagus.
  • Weak muscle contractions during swallowing that slow the rate at which food or stomach acid is cleared from the esophagus.
  • Abnormally strong contractions (spasms) that can cause chest pain or the sensation that food is stuck after swallowing (dysphagia).

Why It Is Done

Tests on the esophagus are done to:

• Help determine whether chest pains may be caused by GERD.
• Help determine the cause of GERD symptoms for people who have not been helped by treatment, who have unusual symptoms, or whose esophagus looks normal during an endoscopy test.
• Monitor the effectiveness of treatment for GERD.
• Detect spasms of the esophagus, which can cause chest pain, and problems with the ability of the esophagus to move food down to the stomach (motility problems).
• Determine whether the esophagus is functioning normally.

How To Prepare

To prepare for an esophagus test:

• Do not take antacids (such as Tums or Rolaids) or acid reducers (such as Axid, Pepcid, Tagamet, or Zantac) for 24 hours before the test unless the test is being done to evaluate the effectiveness of these medicines.
• Stop taking other medicines-such as the proton pump inhibitors lansoprazole (Prevacid), omeprazole (Prilosec), pantoprazole (Protonix), esomeprazole (Nexium), or rabeprazole (Aciphex)-before testing. Your health professional will give you specific instructions.
• Do not drink alcohol or smoke for 24 hours before the test.
• Do not eat or drink for 8 to 12 hours before testing.
• Tell your health professional if you have any other problems, such as enlarged esophageal blood vessels (esophageal varices), heart failure, or other heart conditions.

Talk to your health professional about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results may indicate. To help you understand the importance of this test, fill out the medical test information form(What is a PDF document?).