Gastroparesis Diagnosis

Gastroparesis is diagnosed by confirming that the stomach empties too slowly when nothing is blocking it. A doctor reviews your symptoms and medical history, checks that no obstruction is present, and then orders a test that measures the speed of emptying.

How is gastroparesis diagnosed?

Diagnosis begins with a conversation. According to the National Institute of Diabetes and Digestive and Kidney Diseases, your doctor will ask about your symptoms, your current medicines, and your past and present health problems. A physical exam follows. Because the symptoms overlap with conditions such as reflux, ulcers, and a physical blockage, the doctor first rules out anything obstructing the stomach. Once a blockage is ruled out, a test that measures how fast the stomach empties confirms the diagnosis.

What is a gastric emptying study?

The gastric emptying study, also called gastric emptying scintigraphy, is the main test for gastroparesis. You eat a bland meal, usually eggs or an egg substitute, that contains a small and safe amount of radioactive material. A scanner then tracks how quickly the meal leaves the stomach, and the scan usually takes about four hours. If a large share of the meal still remains in the stomach after four hours, it confirms delayed emptying. The amount of radiation is very low, similar to other routine imaging tests.

What other tests are used to diagnose gastroparesis?

Several other tests can measure emptying or rule out other problems.

• A gastric emptying breath test has you eat a meal containing a substance that is absorbed and later passed into your breath; measuring it shows how fast the stomach empties.
• A wireless motility capsule is a small electronic device you swallow that records how fast food moves through the stomach and intestines; the SmartPill, the wireless motility capsule long used for this test, was discontinued in 2023, and newer capsules such as the Atmo capsule are emerging as replacements, though availability varies by center.
• An upper GI endoscopy looks directly inside the upper digestive tract, while an upper GI series with barium and an abdominal ultrasound can reveal a blockage or other cause.

Your doctor chooses the tests that fit your situation and what is available.

How do you prepare for a gastric emptying test?

Preparation is straightforward, but a few steps matter. You will usually be asked not to eat for several hours before the test so the stomach starts empty. Some medications slow the stomach and can affect the results, so your doctor may ask you to pause them beforehand. Never stop a prescribed medicine on your own; follow the instructions your care team gives you. If you have diabetes, the staff will check that your blood sugar is in a safe range first, because high blood sugar can slow emptying and skew the reading.

What does a gastroparesis diagnosis confirm?

A diagnosis confirms that the stomach is emptying too slowly without a physical blockage, which explains the nausea, fullness, and other symptoms. The test results also show how severe the delay is, and that helps guide treatment. A clear diagnosis is often a relief after months of unexplained symptoms, because it points toward a plan. The next steps usually combine diet changes, medication, and treatment of any underlying cause. See gastroparesis treatment and the gastroparesis diet for what comes next.

Sources

Reviewed by Owen Hastings. NIDDK (National Institute of Diabetes and Digestive and Kidney Diseases), Diagnosis of Gastroparesis (niddk.nih.gov), last reviewed January 2018, for the diagnostic process, the gastric emptying scan, the breath test, the wireless motility capsule, endoscopy, and imaging. Mayo Clinic, Gastroparesis (mayoclinic.org), for test preparation and interpretation. Becker's ASC, Medtronic to discontinue GI SmartPill after 17 years (beckersasc.com), 2023, for the SmartPill discontinuation. This page is general health information, not medical advice. Talk to your doctor about your own care. Last reviewed July 2026.