What Is a Gastric Emptying Scan?

A gastric emptying scan (GES) is a medical test. It is also called a gastric emptying study or gastric emptying scintigraphy. It is a nuclear medicine test, meaning it uses small amounts of radiation. For this reason, this test is usually done in the Nuclear Medicine department of your hospital on an inpatient or outpatient basis.

Symptoms that may call for a gastric emptying scan procedure
Verywell / Gary Ferster

Purpose of Test

A gastric emptying scan may be ordered to help your doctor determine the cause of a number of symptoms involving the digestive tract. Symptoms and reasons for giving the test include:

  • abdominal pain
  • nausea and vomiting
  • feeling full after eating only a small amount of food
  • failure to gain weight (children)
  • prep for certain surgical procedures such as a colectomy
  • to evaluate for gastroesophageal reflux disease (GERD) particularly reflux that has been unresponsive to therapy
  • suspected gastroparesis
  • suspected rapid gastric emptying (you're moving food too quickly through your stomach)

Risks and Contraindications

Before having a gastric emptying scan you should notify your doctor of any food or medication allergies that you have. You will also be instructed to stop eating and drinking for a period of time (about four hours) prior to your test. It is important that you follow these instructions to ensure accurate test results.

Certain medications should be stopped prior to a GES. These include any medication that can affect the way your stomach processes food. While this list is not all inclusive some medications that should be discontinued before this test are:

  • metoclopramide
  • erythromycin
  • tegaserod
  • domperidone
  • narcotic pain relievers such as oxycodone, hydrocodone, morphine, and more
  • atropine
  • dicyclomine
  • loperamide
  • promethazine

Additionally if you have diabetes and use insulin you will be given specific instructions regarding your glucose levels and your insulin dose may need to be adjusted.

If you are a menstruating woman, having this test done during days one to 10 of your monthly cycle may provide more accurate results—hormonal changes affect the rate at which your stomach normally empties.

If your doctor has ordered other testing around the same time as your GES, you should know that you cannot have a barium test within 48 hours of a GES.

If your child is having a GES you will want to simply explain what will happen to them beforehand to help alleviate anxiety. It can also be helpful to take a comfort item such as a favorite toy or a blanket with you. Most children's hospitals have staff on-hand who specialize in relieving a child's anxiety and discomfort when it comes to medical services. Don't hesitate to request these kinds of services.

The Test

A gastric emptying scan is not usually painful or uncomfortable in any way, although some people (including small children) may experience the anxiety of being in a strange environment or interacting with medical personnel.

Before the Test

Before a GES, your doctor will have you eat. If your doctor orders solid food for you before your scan, the standard meal consists of scrambled egg whites, toast with jam, and a small glass of water. The meal has to be the same so that the test results are accurate. The scrambled egg whites contain a radioactive isotope called Technetium-99m Sulfur Colloid which is tasteless. If possible, this meal should be eaten within a time period of 10 minutes.

During the Test

After the meal has been eaten, you will lie down on a table and images of your abdomen will be taken with a special camera. The pictures are taken at various time intervals to see how much of the food has been eliminated from the stomach and how long it takes.

Typically images will be taken 30 minutes, one hour, two hours and four hours after you have eaten the meal.

You may be allowed to leave the nuclear medicine department and return in time to have more images taken at these various times. This means that in total one GES takes approximately four and a half to five hours.

Sometimes a liquid meal is ordered instead of a solid meal. This may be because of the specific condition that your doctor is trying to diagnose with the test or simply because the test is being done on an infant or individual who normally consumes a liquid diet. In this case, the test procedure is similar but the radioactive isotope is simply added to water, formula, or milk and the intervals that pictures are taken at are much closer together.

The overall time the test takes is typically much shorter when using a liquid diet than a solid diet (approximately one hour versus four hours or more).

After the Test

There are very few possible complications of this test that may affect your overall health. However, allergic reaction is always possible (either to the meal or the radioactive isotope). The risk is mitigated by informing your medical team of any known allergies before the test.

Some individuals may be concerned about being exposed to radiation during this test since radiation exposure has been linked to cancer. The biggest factors that contribute to this risk are the amount of radiation you are exposed to, the length of time you are exposed to it, and how frequently you are exposed (having the test only one time versus having many tests or procedures that use radiation).

It is thought that infrequent low doses of radiation typically used for medical procedures pose minimal risk. GES, however, is not generally recommended for pregnant women because of potential risk to the fetus. Breastfeeding women can have GES, but they are advised not to nurse for a brief period after the scan. The risk-to-benefit ratio should also be considered when giving the test to children. If you are concerned about radiation exposure, you should discuss it with your physician prior to scheduling a GES.

Interpreting Results

Certain factors can limit how accurate your results are. These include poor blood sugar control if you are diabetic, not finishing your meal within the 10 minute time frame or not finishing the meal completely, or vomiting during the test.

How long it takes to get the results of this test are variable. A specialist called a radiologist generally interprets the images and then writes a report which is given to your doctor.

Was this page helpful?

Article Sources

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial policy to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Vasavid P, Chaiwatanarat T, Pusuwan P et al. Normal Solid Gastric Emptying Values Measured by Scintigraphy Using Asian-style Meal:A Multicenter Study in Healthy Volunteers. J Neurogastroenterol Motil. 2014;20(3):371-378. doi:10.5056/jnm13114

  2. Knight L. Update on Gastrointestinal Radiopharmaceuticals and Dosimetry Estimates. Semin Nucl Med. 2012;42(2):138-144. doi:10.1053/j.semnuclmed.2011.11.001

  3. Van Leeuwen A, Bladh M. Davis's Comprehensive Manual Of Laboratory And Diagnostic Tests With Nursing Implications. F.A. Davis; 2019.

  4. Alipour Z, Khatib F, Tabib S et al. Assessment of the Prevalence of Diabetic Gastroparesis and Validation of Gastric Emptying Scintigraphy for Diagnosis. Malecular Imaging and Radionuclide Therapy. 2017;26(1):17-23. doi:10.4274/mirt.61587

Additional Reading