How Doctors Diagnose Acid Reflux and GERD

Medically Reviewed By William C. Lloyd III, MD, FACS
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Most people experience acid reflux, or heartburn, from time to time. But if you experience heartburn over the course of a few weeks, it could be a more serious type of acid reflux called GERD (gastroesophageal reflux disease). Left untreated, GERD can cause problems with the esophagus and breathing. If you’re concerned you may have acid reflux or GERD, talk with your doctor for an accurate diagnosis. 

Acid Reflux Diagnosis

To diagnose acid reflux, your doctor will review your medical history and ask about your symptoms. Your doctor may suggest making some changes to your diet, lifestyle or medicines. If these treatments don’t help, you may need testing for GERD.

GERD Diagnosis

If your doctor suspects you may have GERD, he or she may recommend one or more tests to help diagnose it. In some cases, your doctor may use these tests to see whether GERD has caused any other health conditions, such as problems with your esophagus. 

Tests to Diagnose GERD

Your doctor can use the results of these tests to find out whether you have GERD and decide the best type of treatment: 

Upper gastrointestinal (GI) endoscopy.  This test looks inside your digestive tract. Your doctor may recommend it if you have moderate to severe acid reflux. You can expect:

  • Before the test, you may get a sedative to help you relax and keep you comfortable during the test. You will also get an anesthetic to numb the back of your throat.

  • Your doctor places a small tube, called an endoscope, down your throat. A small camera at the end of the tube lets your doctor look for any problems caused by GERD.

  • Your doctor may also take a small piece of tissue from the lining of your esophagus, called a biopsy. This checks to see whether GERD has caused any problems in your esophagus.

Upper GI series.  This test consists of a series of X-rays of your upper digestive tract. During the X-rays, you will drink a chalky liquid called barium. The barium coats the lining of your digestive tract so your doctor can see problems related to GERD, such as a narrowing in your esophagus, ulcers, or hiatal hernias. 

Esophageal pH and impedance monitoring. This test measures how much acid is in your esophagus as you go through a normal day. For this test:

  • Your doctor places a tube through your mouth and into your esophagus. The upper part of the tube gets taped to your cheek and is left there for 24 hours.

  • A sensor at the bottom of the tube monitors how much acid comes into your esophagus. A monitor records the readings from the sensor.

  • Your doctor may also ask you to keep a diary of the types of foods you eat and your GERD symptoms to see how different foods and the time of day affect the acid.

  • Your doctor removes the tube after 24 hours.

Wireless esophageal pH monitoring. This test is another way to measure how much acid is in your esophagus:

  • During an upper GI endoscopy, your doctor places a small capsule on the wall of your esophagus. The capsule is about the size of a pencil eraser. It has a pH sensor, battery, and a transmitter. The capsule records the pH levels in your esophagus and sends the information to a small receiver you wear on a belt.

  • When you have symptoms of GERD, you press a small button on the receiver.

  • Your doctor may also ask you to record some of your daily activities, such as when you eat and drink, lie down, and get up.

  • Most people wear the monitor for about 48 hours. The capsule will detach on its own and pass through your digestive system.

Esophageal manometry. This test measures muscle movement in your esophagus. It can be done right in your doctor’s office: 

  • Your doctor sprays an anesthetic on the back of your throat to numb the area.

  • A thin tube passes through your nose and into your esophagus.

  • A computer will measure how strong the muscle contractions are in different areas of your esophagus.

This test can tell whether your GERD is due to a weak muscle connecting your esophagus to your stomach or whether you have other esophagus problems. 
If you have GERD, your doctor will likely recommend diet and lifestyle changes as the first step towards managing the condition. You may also benefit from medicines that control the amount of acid in your stomach or the movement of your upper GI tract, respectively.

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Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2021 May 10
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THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.

  1. Diagnosis of gastroesophageal reflux (GER) and gastroesophageal reflux disease (GERD). National Institute of Diabetes and Digestive and Kidney Diseases.

  2. Gastroesophageal reflux (GER) and gastroesophageal reflux disease (GERD) in adults. National Institute of Diabetes and Digestive and Kidney Diseases.

  3. Katz PO, Gerson LB, Vela MF. Guidelines for the diagnosis and management of gastroesophageal reflux disease. Am J Gastroenterol. 2013;108:308-328. 

  4. Gastroesophageal Reflux Disease (GERD). Johns Hopkins Medicine. 

  5. Esophageal pH Monitoring. John Hopkins Medicine.