Gastric Emptying Study: Why It Matters for Your Ozempic Claim

If you developed gastroparesis after taking Ozempic, Wegovy, Mounjaro, or another GLP-1 receptor agonist, one diagnostic test stands above all others in its importance to your legal claim: the gastric emptying study (GES). This test provides objective, quantifiable evidence that your stomach is not functioning normally — evidence that is difficult for defendants to dispute and that significantly strengthens your position in the GLP-1 litigation.

Understanding what a gastric emptying study is, how it works, and what results you need is essential for anyone considering or pursuing a legal claim.

What Is a Gastric Emptying Study?

A gastric emptying study, also called gastric emptying scintigraphy, is a nuclear medicine test that measures how quickly food moves from your stomach into your small intestine. It is considered the gold standard diagnostic test for gastroparesis by the American Gastroenterological Association and other leading medical organizations.

The test directly measures your gastric motility — the ability of your stomach muscles to contract and push food through your digestive system. When GLP-1 drugs cause gastroparesis, they slow or paralyze these contractions, and the gastric emptying study captures this impairment in objective, measurable data.

How the Test Is Performed

The gastric emptying study is a non-invasive outpatient procedure that typically takes about four hours. Here is what to expect:

Preparation

• You will need to fast for at least 8-12 hours before the test (typically overnight)
• Your doctor may instruct you to stop certain medications that affect gastric motility before the test, including proton pump inhibitors, prokinetic agents, and — importantly — the GLP-1 drug itself. Follow your doctor’s specific instructions.
• Inform your doctor if you are pregnant or have any allergies

The Procedure

1. You eat a standardized meal. The standard protocol in the United States uses a meal of egg whites (or an egg substitute), toast, jam, and water. A small amount of technetium-99m sulfur colloid — a safe, low-dose radioactive tracer — is mixed into the egg portion.

2. Imaging begins. Immediately after you finish the meal, you stand or sit in front of a gamma camera, which detects the radioactive tracer in your stomach. The camera takes images at specific intervals.

3. Timed measurements. Images are taken at 1 hour, 2 hours, 3 hours, and 4 hours after the meal. At each interval, the camera measures how much of the radiolabeled food remains in your stomach.

4. You wait between images. Between imaging intervals, you can sit in the waiting area. You should not eat or drink anything additional during the test.

Understanding the Results

The results are expressed as the percentage of food retained in the stomach at each time point. The key measurement is the 4-hour retention rate:

• Normal: Less than 10% of the meal remaining in the stomach at 4 hours
• Mild gastroparesis: 10-15% retention at 4 hours
• Moderate gastroparesis: 15-35% retention at 4 hours
• Severe gastroparesis: Greater than 35% retention at 4 hours

Results at the 1-hour and 2-hour marks also provide useful information, but the 4-hour measurement is the primary diagnostic criterion recognized by the American Gastroenterological Association.

Why the GES Is Critical for Your Legal Claim

In the GLP-1 litigation, the gastric emptying study serves as the single most important piece of medical evidence for gastroparesis claims. Here is why:

Objective Evidence

Unlike symptom reports alone — which defendants can argue are subjective or attributable to other causes — a gastric emptying study produces quantifiable, reproducible data. The test shows exactly how impaired your gastric motility is, measured in precise percentages. This type of evidence is difficult to dismiss in litigation.

Establishes the Diagnosis

Gastroparesis is defined by delayed gastric emptying. Without a GES, the diagnosis relies on symptoms and clinical judgment, which defendants can challenge. With a GES, the diagnosis is confirmed by an objective measurement that meets the accepted medical standard.

Strengthens Causation

The GLP-1 drugs’ mechanism of action — slowing gastric emptying — is well-documented. A GES showing delayed emptying in a patient who took a GLP-1 drug creates a direct link between the drug’s known mechanism and the patient’s documented injury. This connection is central to proving causation.

Case Tier Classification

In mass tort settlements, cases are typically assigned to tiers based on the strength of the evidence and severity of the injury. Cases with a confirmed GES showing moderate to severe gastroparesis are generally placed in higher tiers, which translates to higher compensation. Cases without a GES may be placed in lower tiers or may face challenges establishing eligibility.

What If You Have Not Had a GES Yet?

If you have been diagnosed with gastroparesis based on symptoms alone, or if you suspect you have gastroparesis but have not been formally diagnosed, getting a gastric emptying study should be a priority — both for your medical care and your legal claim.

Steps to take:

1. Ask your gastroenterologist. Request a gastric emptying study referral. Explain your symptoms and your history of GLP-1 drug use. Most gastroenterologists will agree that a GES is appropriate for a patient with gastroparesis symptoms.

2. Use the standard protocol. Ensure the test uses the 4-hour protocol with the standardized egg-white meal. Shorter protocols (1-hour or 2-hour studies) are less reliable and may not be accepted as strong evidence in the litigation.

3. Follow preparation instructions carefully. Fasting and medication adjustments before the test are important for accurate results. An improperly prepared test may need to be repeated.

4. Obtain your results. Request a copy of the full GES report, including the retention percentages at each time point and the radiologist’s interpretation. Share this with your attorney.

Other Diagnostic Tests

While the gastric emptying study is the gold standard, other tests may supplement your medical record:

• Upper endoscopy (EGD) — can reveal food retention in the stomach and rule out mechanical obstruction
• SmartPill (wireless motility capsule) — an ingestible capsule that measures pressure, pH, and transit time through the entire GI tract, approved by the FDA as an alternative to GES
• Electrogastrography (EGG) — measures the electrical signals that control stomach contractions, though this test is less widely available and less commonly used in clinical practice
• Upper GI series (barium swallow) — can show delayed emptying, though it is less precise than scintigraphy

These tests can provide additional supporting evidence, but none carries the same weight as the standard 4-hour gastric emptying scintigraphy in the context of the litigation.

Frequently Asked Questions

Is the gastric emptying study painful?

No. The test is non-invasive. You eat a meal and then have images taken at intervals. The radioactive tracer used is at a very low dose and is considered safe. The main inconvenience is the time commitment — approximately 4 hours.

How much does a gastric emptying study cost?

The cost varies but is typically covered by health insurance when ordered by a physician for a patient with gastroparesis symptoms. Without insurance, the cost can range from several hundred to over a thousand dollars. Given its importance to both your health and your legal claim, it is a worthwhile investment.

Can I have a GES if I am still taking my GLP-1 medication?

Your doctor will advise whether to discontinue the medication before the test. In some cases, the GES is performed while the patient is still on the drug to document the current state of gastric function. In other cases, the drug is discontinued first to see whether gastroparesis persists independently. Both scenarios can provide valuable information.

What if my GES results are normal?

A normal GES does not necessarily mean you do not have a claim, but it does mean that gastroparesis may not be the basis of your case. Other injuries — such as bowel obstruction, gallbladder disease, or pancreatitis — may still qualify. Discuss your full medical history with your attorney.

How recent does my GES need to be?

There is no strict cutoff, but a GES performed while you were symptomatic — ideally during or shortly after your GLP-1 drug use — is most persuasive. If you had a GES years ago, it may still be relevant. If you have not had one, getting one now is better than not having one at all.

Take the Next Step

The gastric emptying study is the cornerstone of a strong GLP-1 gastroparesis claim. If you developed stomach problems after taking Ozempic, Wegovy, Mounjaro, or another GLP-1 drug, getting this test done serves both your medical interests and your legal interests. Do not wait.

If you or a loved one has been affected, request a free case review today.

Advertisement. This content is provided for informational purposes only and does not constitute legal advice. NuLegal | Ashkaan Hassan, Esq. | CA Bar #283629