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FDA GLP-1 Gastroparesis Warning 2026: What Patients Need to Know

April 9, 20269 min readMedSwitcher Editorial Team

In March 2026, the FDA mandated updated safety labels for all injectable semaglutide and tirzepatide products to include information about gastroparesis — a condition where the stomach empties food abnormally slowly. If you take Ozempic, Wegovy, Mounjaro, or Zepbound, this affects you. If you take Foundayo, it does not. Here's what you need to know.

What the FDA Actually Did

On March 14, 2026, the FDA issued a supplemental safety labeling update requiring manufacturers of semaglutide-based and tirzepatide-based medications to add gastroparesis-related language to their prescribing information and patient medication guides. The compliance deadline for updated labels is June 15, 2026.

This is not a recall. This is not a black box warning. This is an updated safety label — the same type of change the FDA makes routinely as post-market surveillance data accumulates. It means the FDA believes prescribers and patients should be explicitly informed about gastroparesis risk when starting or continuing these medications.

Which Medications Are Affected

The label update applies to:

  • Ozempic (semaglutide injection, for type 2 diabetes)
  • Wegovy (semaglutide injection, for weight management)
  • Mounjaro (tirzepatide injection, for type 2 diabetes)
  • Zepbound (tirzepatide injection, for weight management)

What about Foundayo? Foundayo (orforglipron) was not included in this label update. There are two reasons: first, Foundayo was approved after the adverse event data collection period that triggered this review. Second, Foundayo is a non-peptide small molecule GLP-1 receptor agonist — a fundamentally different class of drug from the peptide-based injectables. While it activates the same receptor, its pharmacokinetic profile and mechanism differ in ways that may influence gastroparesis risk. The FDA has stated it will monitor Foundayo separately as real-world data accumulates. For more details, see our Ozempic to Foundayo switch guide.

What Is Gastroparesis?

Gastroparesis literally means "stomach paralysis." It's a condition where the muscles of the stomach don't contract normally, causing food to remain in the stomach far longer than it should. The result is a cluster of symptoms:

  • Persistent nausea — not the transient nausea common during GLP-1 titration, but ongoing nausea that doesn't resolve
  • Vomiting — particularly of undigested food hours after eating
  • Severe bloating and abdominal distension
  • Early satiety — feeling extremely full after only a few bites
  • Abdominal pain
  • Unintentional weight loss from inability to eat adequate nutrition

Gastroparesis ranges from mild (manageable with dietary modifications) to severe (requiring hospitalization or surgical intervention). Most GLP-1-associated cases identified in the FDA review were mild to moderate.

The Actual Numbers

The FDA's review found that gastroparesis adverse event reports among patients using semaglutide or tirzepatide for more than 12 months increased from approximately 0.1% to 0.4%. That means roughly 4 in every 1,000 long-term users reported gastroparesis symptoms serious enough to be documented as an adverse event.

For context:

  • The background rate of gastroparesis in the general population is approximately 0.02-0.04%
  • The rate among people with type 2 diabetes (regardless of medication) is already elevated at approximately 0.05-0.1%
  • The GLP-1-associated rate of ~0.4% represents a meaningful but modest increase above these baselines

The increase was statistically significant, which is why the FDA acted. But it's important to maintain perspective: 99.6% of long-term users did not report gastroparesis.

Normal GI Side Effects vs. Red Flags

GLP-1 medications routinely cause gastrointestinal side effects — that's partly how they work. The challenge is distinguishing normal titration-phase GI discomfort from something more concerning. For a comprehensive overview of GLP-1 side effects, see our GLP-1 side effects guide.

Normal (Expected) GI Side Effects

  • Mild to moderate nausea during the first 2-4 weeks of a new dose
  • Occasional loose stools or constipation
  • Reduced appetite (this is the intended effect)
  • Mild bloating that resolves within a few weeks

Red Flags — Contact Your Doctor

  • Persistent nausea or vomiting beyond 6 weeks after reaching a stable dose
  • Vomiting undigested food several hours after eating
  • Severe bloating or abdominal distension that doesn't improve
  • Inability to eat — if you physically cannot consume enough food to function
  • Unintentional weight loss beyond what's expected from the medication
  • New symptoms appearing after months of tolerating the medication without issues

The key distinction: normal GLP-1 side effects typically emerge during dose titration and improve over time. Gastroparesis symptoms tend to persist or worsen, particularly after you've been on a stable dose for an extended period.

What You Should Do Right Now

Do not stop your medication without talking to your doctor. Abruptly discontinuing GLP-1 medications can cause rebound weight gain and, for diabetes patients, dangerous blood sugar spikes. The risk-benefit calculation still overwhelmingly favors continued use for most patients.

Instead:

  1. Be aware of symptoms. Now that you know what to watch for, pay attention to GI symptoms — especially any that develop after you've been on a stable dose
  2. Report concerns promptly. If you experience persistent nausea, vomiting, or bloating beyond the normal titration window, contact your prescriber
  3. Keep a symptom log. Track when symptoms occur relative to meals and doses. This information helps your doctor distinguish gastroparesis from other causes
  4. Know your risk factors. Pre-existing diabetes, prior GI surgery, and certain autoimmune conditions increase gastroparesis risk independently
  5. Discuss alternatives if needed. If you're concerned, ask your doctor about Foundayo — a different-mechanism oral GLP-1 not covered by this warning

Bottom Line

The FDA's March 2026 label update is a reasonable, evidence-based safety communication — not a crisis. Gastroparesis risk with long-term GLP-1 use is real but uncommon, affecting roughly 4 in 1,000 long-term users. The vast majority of patients can continue their medication safely. Know the red flags, report symptoms early, and don't make medication changes without medical guidance. If the gastroparesis risk concerns you, switching to Foundayo is worth discussing with your prescriber since it wasn't included in this update.

Sources

  1. FDA. "Safety Labeling Update: Semaglutide and Tirzepatide — Gastroparesis Risk." March 14, 2026.
  2. Camilleri M. "Gastroparesis: Epidemiology, Clinical Features, and Treatment." Gastroenterology. 2022.
  3. FDA Adverse Event Reporting System (FAERS). Cumulative data through Q4 2025.
  4. Eli Lilly. "Foundayo Prescribing Information." April 2026.

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Medical Disclaimer

This article is for informational and educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition or medication. Never disregard professional medical advice or delay seeking it because of something you have read on this website.