Gastric Emptying Study: How to Prepare, What Happens and Normal Results
Updated: 2 days ago
Written and medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: November 2026 · How we review
Quick Answer
A gastric emptying study measures how quickly food and liquid leave the stomach. You eat a small meal containing a trace of radioactive tracer, and a camera takes pictures over up to 4 hours. Emptying that is too slow points to gastroparesis or a blockage; too fast points to dumping syndrome. Fast for at least 4 hours beforehand.
What the research says
The 4-hour scan finds more delayed emptying: a meta-analysis of children who had scans at both 2 and 4 hours found that results changed between the two time points in about 20% of patients, and the full 4-hour study identified an additional 10% with gastroparesis (Shargo R et al., Neurogastroenterology and Motility, 2025) [2]
The scan also tracks treatment: a meta-analysis of 10 studies and 281 patients treated with gastric peroral endoscopic pyloromyotomy (G-POEM) for refractory gastroparesis used 4-hour scintigraphy to show a fall in stomach retention of about 26 percentage points after the procedure, alongside better symptom scores (Uemura KL et al., Endoscopy International Open, 2020) [3]
Key takeaways
Measures how fast a standard meal leaves the stomach; used for nausea, vomiting, early fullness and bloating.
Fast at least 4 hours, avoid smoking, and ask about stopping medicines that slow the gut.
You eat a tracer meal within about 10 minutes; 1-minute scans follow at 1, 2 and 4 hours.
More than 60% retained at 2 hours or more than 10% at 4 hours suggests gastroparesis.
Not done during pregnancy or breastfeeding because of the radiation, even though the dose is small.
What is a gastric emptying study?
After a meal, the stomach grinds food and pushes it into the small intestine at a steady rate. In gastroparesis, the stomach muscles or nerves work poorly and food stays too long; after some stomach surgeries, food can rush through too fast. A gastric emptying study puts numbers on this process so your provider can tell which problem, if any, is causing your symptoms. Sources: [1]
Gastric emptying scintigraphy takes 2–4 hours with short scans in between.
Types of gastric emptying tests
Your provider chooses the method that fits your situation.
Test | How it works | Notes |
Gastric emptying scintigraphy (GES) | Meal with technetium-99m tracer; a gamma camera images the stomach | Most common; solid meal over up to 4 hours |
Liquid emptying study | Tracer-labeled water imaged 3 times over about 1 hour | Normal emptying about 20–25 minutes |
Gastric emptying breath test (GEBT) | Meal labeled with carbon-13; breath samples measure ¹³CO₂ | No radiation |
Wireless motility capsule (SmartPill) | Swallowed sensor sends data to a receiver you wear | Passes in stool within 1–2 days |
Sources: [1]
Why is it done?
Nausea or vomiting that keeps coming back.
Feeling full after a few bites (early satiety), bloating or upper belly pain.
Loss of appetite with weight loss.
Swings in blood sugar in people with diabetes.
Dizziness or a racing heart after meals, which can signal dumping syndrome.
Chronic reflux or indigestion that hasn't responded to treatment. Sources: [1]
How do I prepare?
Fast for at least 4 hours; tests are usually scheduled in the morning.
Don't smoke beforehand, because smoking slows emptying.
Ask whether to pause medicines that affect the gut, such as opioids, some antidepressants, calcium channel blockers, acid-reducing drugs and some hormone therapies. Don't stop anything without advice.
If you use insulin, bring it and your glucose monitor; very high or low sugar can affect results.
Tell your provider if you are pregnant or breastfeeding. Sources: [1]
What happens during the test?
You eat a standard meal of scrambled egg whites mixed with a small amount of tracer, toast with strawberry jam, and water, finishing within about 10 minutes.
A camera takes an image of your stomach for about 1 minute.
More images are taken at 1, 2 and 4 hours (and at 30 minutes if fast emptying is suspected); you can sit, stand or leave the room between scans.
If your stomach is already empty at 2 hours, the test may end early.
A liquid study, if ordered, adds 3 sets of images over about 1 hour. Sources: [1]
The test is painless. The tracer leaves your body in urine and stool over about 2 days; drinking extra water helps. Sources: [1]
Understanding your results
Normal solid-meal values by time point.
Time | Normal | Suggests gastroparesis | Suggests rapid emptying (dumping) |
30 minutes | At least 70% still in the stomach | — | More than 30% emptied |
1 hour | At least 10% emptied, at least 30% remaining | — | More than 70% emptied |
2 hours | At least 40% emptied | More than 60% still in the stomach | — |
4 hours | At least 90% emptied | More than 10% still in the stomach | — |
Sources: [1]
Completing the full 4 hours matters: in children scanned at both time points, the 4-hour study identified an additional 10% with gastroparesis. The same 4-hour measurement is used to track response to treatments such as G-POEM, where retention fell by about 26 percentage points. Sources: [2, 3]
Risks
The radiation dose is small and considered not harmful, but the test is postponed during pregnancy or breastfeeding. There are no other known side effects. Sources: [1]
Conclusion
A gastric emptying study turns symptoms like nausea and early fullness into measurable numbers. Prepare carefully, especially with medicines and blood sugar, and ask whether your test will run the full 4 hours, which detects more cases of delayed emptying.
Keep learning: read about gastroparesis and functional dyspepsia, which can cause similar symptoms with normal emptying.
Frequently asked questions
How long does a gastric emptying study take?
Usually 2 to 4 hours for the solid-meal study, plus about 1 hour if a liquid study is added.
What do I eat during the test?
Usually scrambled egg whites with a small amount of tracer, toast with strawberry jam, and water.
Is the radiation dangerous?
The dose is small and considered not harmful. The tracer leaves the body in about 2 days. The test is avoided during pregnancy and breastfeeding.
What is a normal result?
At 2 hours at least 40% of the meal has left the stomach, and at 4 hours at least 90% has left.
What result suggests gastroparesis?
More than 60% of the meal still in the stomach at 2 hours, or more than 10% at 4 hours.
What does fast emptying mean?
More than 30% emptied at 30 minutes or more than 70% at 1 hour suggests dumping syndrome, often after stomach surgery.
Why does the 4-hour scan matter?
Some people empty normally at 2 hours but not at 4 hours. A meta-analysis found the 4-hour study identified an additional 10% with gastroparesis.
Can I take my medicines before the test?
Ask your provider. Opioids, some antidepressants, calcium channel blockers and acid-reducing drugs may need to be paused for a few days.
I have diabetes. Is anything different?
Bring your insulin and glucose meter. Your sugar is checked and adjusted, because very high or low sugar changes emptying.
Are there alternatives to scintigraphy?
Yes: a carbon-13 breath test or a swallowed wireless motility capsule, neither of which uses radiation.
Related Reading
Gastric Emptying Study in Children (Solid-Meal GES): What to Expect explains the stomach emptying test for children.
Gastroparesis: Symptoms, Causes, Diet & Treatment — Complete Guide the condition a slow result most often points to.
Functional Dyspepsia: Why You Feel Full and Upset Stomach Pain Even When Tests Come Back Normal a common cause of similar symptoms with normal emptying.
Cyclic Vomiting Syndrome: The 4 Phases of Each Episode, Triggers, Treatment and Outlook — What You Need to Know another cause of repeated vomiting the test helps tell apart.
Hydrogen Breath Test: How to Prepare, What Happens and What Results Mean a related breath test used for gut symptoms.
Upper GI Series: What It Is, Why It's Done, How to Prepare and What to Expect an X-ray test that can show a blockage slowing emptying.
References
Cleveland Clinic. Gastric Emptying Study: What It Is, Prep, Procedures & Results. Cleveland Clinic. Last updated September 20, 2023. https://my.clevelandclinic.org/health/diagnostics/gastric-emptying-study
Shargo R, Luongo M, Mhaskar R, et al. Assessing the clinical value of 2-h versus 4-h gastric emptying scintigraphy in pediatrics: a systematic review and meta-analysis. Neurogastroenterology and Motility. 2025;37(2):e14978. PMID 39638920. https://doi.org/10.1111/nmo.14978
Uemura KL, Chaves D, Bernardo WM, et al. Peroral endoscopic pyloromyotomy for gastroparesis: a systematic review and meta-analysis. Endoscopy International Open. 2020;8(7):E911-E923. PMID 32617395. https://doi.org/10.1055/a-1119-6616
Medical disclaimer
This article is for general education only and does not replace advice from a qualified healthcare professional. Talk to your doctor about your own diagnosis and treatment, and seek emergency care right away for severe or sudden symptoms.
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