Diagnosis of gastroparesis (GP) may begin with various tests. This will determine if there is anything preventing the stomach from emptying properly. These tests will find if the GP symptoms are caused by another condition.
This may include:
- imaging tests (such as CT scans or x-rays)
- blood tests
- upper endoscopy
- an ultrasound, which uses sound waves that create images to look for disease in the pancreas or gallbladder that may be causing symptoms.
An endoscope, a long flexible tube with a camera and light on the end, is used in an endoscopy. An endoscopy involves placing this tube in the mouth, down the esophagus, and into the stomach and duodenum. The duodenum is the first part of the small intestine. This tube has a camera and light on the end allowing the healthcare provider to see inside your GI tract and make sure an ulcer, cancer or other findings are not the reason for the symptoms noted above.
Your healthcare provider will decide what test is right for you. This decision is based on the severity of your symptoms, any medications you take, availability, and other conditions you have. The following tests are commonly used in the diagnosis of GP. Drugs (medications) that are being taken should also be reviewed prior to testing as some of them may interfere with test result.
If – after a review of the symptoms, history, and examination – the doctor suspects gastroparesis, a test to measure how fast the stomach empties is required to confirm the diagnosis.
Slow gastric emptying alone does not correlate directly with a diagnosis of gastroparesis. (Pasricha PJ, et al. Clin Gastroenterol Hepatol. 2011 July.)
Stomach Emptying Tests
There are several different ways to measure the time it takes for food to empty from the stomach into the small intestine. These include scintigraphy, wireless motility capsule, or breath test. Your doctor will provide details of the one chosen.
Gastric Emptying Scintigraphy (GES)
The diagnostic test of choice for gastroparesis is a gastric emptying study (scintigraphy). The test is done in a hospital or specialty center.
A gastric emptying scintigraphy involves eating a meal with a small amount of radioactive substance. This allows images to be taken during digestion, determining the rate of stomach emptying.
Typically, the meal includes eggs, butter, jam and toast. People with allergies to those foods will have a modified meal which should contain the same contents and calories of the original standard meal. The meal should be completely ingested. The test can take between 2 and 4 hours to complete. The test will give the most accurate results if it is done for the full four hours.
A diagnosis of gastroparesis is confirmed when 10% or more of the meal is still in the stomach after 4 hours.
Wireless Motility Capsule
This is a piece of equipment in the form of a pill. This pill is swallowed and then travels through the GI tract. It will measure temperature, contractions of the entire gut as the pill moves down, and the pH levels (acidity and alkalinity) of the GI tract. This information is collected by wearing a receiver over 5 days that records the data. This test also measures the amount of time the GI tract takes as it moves contents through the gut.
Gastric Emptying Breath Test (GEBT)
This test is done using breath samples that are collected. To begin the test the patient eats a meal that contains a nonradioactive ingredient. This allows the food to be tracked and measured in your breath over a few hours. This test can be done in a doctor’s office or at home and can show how quickly the stomach empties.
Updated October 2023
Adapted from IFFGD Publication: Gastroparesis Overview by: Baharak Moshiree MD MSc, Mackenzie Jarvis PA-C, DMs, Atrium Health, Wake Forest, Digestive Health-Morehead Medical Plaza; Marissa Lombardi, International Foundation for Gastrointestinal Disorders, Mt. Pleasant, SC