Guides / Safety and status
Pancreatitis and gallbladder problems on a GLP-1: how common, and what to watch for
Both are listed as serious warnings on every GLP-1 label. Both are uncommon. The symptoms are worth knowing, because the early signs look like ordinary GLP-1 stomach upset.
[00] Short answer
- Gallstones (cholelithiasis) were reported by 1.6% of adults on Wegovy injection vs 0.7% on placebo, and by 1.1% on Zepbound vs 1%1–2.
- Gallbladder inflammation (cholecystitis): 0.6% on Wegovy vs 0.2%, and 0.7% on Zepbound vs 0.2%1–2.
- Pancreatitis was confirmed in 0.2% of people on Zepbound and 0.2% on placebo in the weight trials, and in 4 people on Wegovy vs 1 on placebo1–2.
- The main pancreatitis symptom is severe stomach pain that won't go away, sometimes felt through to the back. The labels say to stop the medicine and call your provider right away1–2.
How common is pancreatitis on Wegovy, Ozempic, Mounjaro or Zepbound?
Pancreatitis is uncommon on GLP-1s. In the Zepbound weight trials it was 0.2% on tirzepatide and 0.2% on placebo. In the Wegovy weight trials it was confirmed in 4 people on semaglutide (0.2 cases per 100 patient-years) and 1 on placebo1–2.
| Medicine and trials | On the medicine | Comparison group | Note |
|---|---|---|---|
| Wegovy, weight trials1 | 4 people (0.2 per 100 patient-years) | 1 person (under 0.1) | Confirmed by an expert panel (adjudicated) |
| Zepbound, weight trials2 | 0.2% (0.14 per 100 years) | 0.2% (0.15 per 100 years) | Adjudicated |
| Zepbound, sleep apnea trials2 | 0.84 per 100 years | 0 | Adjudicated |
| Ozempic, diabetes trials3 | 7 people (0.3 per 100 patient-years) | 3 people (0.2) | Comparator, not only placebo |
| Mounjaro, diabetes trials4 | 13 people (0.23 per 100 years) | 3 people (0.11) | Comparator, not only placebo |
Per 100 patient-years means cases for every 100 people treated for a year. Each label says rates can't be compared across different drugs' trials.
The UK Wegovy SmPC gives 0.2% for semaglutide 2.4 mg vs under 0.1% on placebo5. Every US label adds that pancreatitis, including fatal and non-fatal hemorrhagic or necrotizing (tissue-destroying) forms, "has been observed" in people on GLP-1 medicines1–4.
In the UK, the MHRA received 1,296 Yellow Card reports of pancreatitis with GLP-1 medicines between 2007 and October 2025. Of these, 19 were fatal and 24 were necrotizing. For scale, about 25.4 million packs were dispensed in the past 5 years7. Yellow Card reports are suspected cases, so they don't give a true rate.
How common are gallstones and gallbladder problems on a GLP-1?
Gallstones and gallbladder inflammation happen more often on GLP-1s than on placebo. On Wegovy injection, 1.6% of adults had gallstones vs 0.7% on placebo. On Zepbound, 1.1% vs 1%, with gallbladder inflammation at 0.7% vs 0.2%1–2.
| Medicine and trials | Gallstones | Gallbladder inflammation | Placebo |
|---|---|---|---|
| Wegovy injection, adults1 | 1.6% | 0.6% | Placebo: 0.7% and 0.2% |
| Wegovy tablets, adults1 | 2.5% | Not given | Placebo: 1% |
| Wegovy injection, ages 12+1 | 3.8% | 0.8% | Placebo: 0% and 0% |
| Zepbound, weight trials2 | 1.1% | 0.7% | Placebo: 1% and 0.2%. Gallbladder removed: 0.2% vs 0 |
| Ozempic 0.5 mg / 1 mg3 | 1.5% / 0.4% | Not given | Placebo: 0% |
| Mounjaro, diabetes trials4 | 0.6% (all acute gallbladder disease) | Not given | Placebo: 0% |
Mounjaro's 0.6% groups gallstones, biliary colic and gallbladder removal. Compare each medicine only with its own placebo.
The UK Mounjaro SmPC reports acute gallbladder disease in 2.0% on tirzepatide vs 1.6% on placebo in the pooled SURMOUNT-1 to -3 weight trials, with gallbladder inflammation at 0.6% vs 0.2%6.
Does fast weight loss cause it? Partly. The Zepbound label says gallbladder events "were associated with weight reduction"2. The Wegovy label says rapid weight loss can raise the risk of gallstones, but gallbladder problems were still more common on Wegovy than placebo "even after accounting for the degree of weight loss"1. It also says gallbladder disease can happen without rapid weight loss1.
What are the symptoms of pancreatitis and gallbladder problems on a GLP-1?
For pancreatitis, the Wegovy and Zepbound Medication Guides describe "severe pain in your stomach area (abdomen) that will not go away, with or without nausea or vomiting", and say "sometimes you may feel the pain from your abdomen to your back"1–2.
For gallbladder problems, the same guides list1–2:
- pain in your upper stomach (abdomen)
- fever
- yellowing of your skin or eyes (jaundice)
- clay-colored stools
The MHRA points out that early pancreatitis can be hard to spot, because pain, nausea or vomiting can be put down to normal GLP-1 stomach side effects7. What sets pancreatitis apart in the labels is pain that is severe and doesn't go away1–2. For everyday stomach effects, see GLP-1 side effects.
When do the labels say to stop and get help?
| Problem | US labels | UK |
|---|---|---|
| Suspected pancreatitis | Stop the medicine and call your healthcare provider right away1–2 | Seek immediate medical attention. Stop the medicine6–7 |
| Confirmed pancreatitis | No separate rule. The labels say to stop if pancreatitis is suspected2,4 | Do not restart5–7 |
| Gallbladder symptoms | Call your provider (Wegovy) or tell them right away (Zepbound). Some gallbladder problems need surgery1–2 | Listed as a side effect in section 4.85–6 |
| Past pancreatitis | Not listed as a contraindication2,4 | Not studied. Use with caution5–7 |
The labels don't tell you to stop the medicine for gallbladder symptoms. They say your provider may order gallbladder tests and follow-up1–2.
Do raised lipase or amylase levels mean pancreatitis?
Not on their own. On Mounjaro, the pancreatic enzymes amylase and lipase rose by an average of 33% to 38% and 31% to 42% from baseline, vs a 4% rise in amylase and no change in lipase on placebo4. The US labels say the meaning of these rises "is unknown in the absence of other signs and symptoms of pancreatitis"2,4.
The UK SmPCs say raised enzymes alone "are not predictive of acute pancreatitis"5–6. If a blood test shows high levels, your prescriber will read them alongside how you feel.
Questions
How common is pancreatitis on Mounjaro or Zepbound?
In the Zepbound weight trials, 0.2% on tirzepatide and 0.2% on placebo had confirmed pancreatitis. In the Mounjaro diabetes trials, 13 people had it (0.23 per 100 years of treatment) vs 3 on comparison drugs (0.11).
Does Wegovy cause gallstones?
Gallstones were more common on Wegovy: 1.6% of adults on the injection vs 0.7% on placebo. The label says rapid weight loss raises the risk, but Wegovy still had more gallbladder problems after allowing for weight loss.
What does GLP-1 pancreatitis pain feel like?
The Medication Guides describe severe pain in the stomach area that will not go away, with or without nausea or vomiting. It can be felt from the abdomen through to the back.
Can I restart my GLP-1 after pancreatitis?
The UK SmPCs and the MHRA say not to restart if pancreatitis is confirmed. The US labels say to stop the medicine if pancreatitis is suspected. Your doctor decides what happens next.
Can I take a GLP-1 if I've had pancreatitis before?
The UK SmPCs say semaglutide and tirzepatide haven't been studied in people with past pancreatitis and should be used with caution. The US labels don't list it as a contraindication. Talk to your prescriber.
Should I stop my GLP-1 if I have gallbladder pain?
The labels say to contact your healthcare provider about upper stomach pain, fever, yellow skin or eyes, or clay-colored stools. They don't say to stop for gallbladder symptoms alone, but severe stomach pain that won't go away needs urgent care.
Sources
Checked against Wegovy (06/2026), Ozempic (05/2026), Zepbound and Mounjaro (08/2026) US prescribing information and Medication Guides, UK SmPCs for Wegovy and Mounjaro (eMC, 2026), and MHRA Drug Safety Update (January 2026). How we check
- 1Wegovy (semaglutide) injection and tablets, US prescribing information and Medication Guide, sections 5.2, 5.3, 6.1 and 17. Novo Nordisk, revised 06/2026
- 2Zepbound (tirzepatide) US prescribing information and Medication Guide, sections 4, 5.4, 5.5 and 6.1. Eli Lilly, revised 08/2026
- 3Ozempic (semaglutide) injection, US prescribing information, sections 5.2, 5.9 and 6.1. Novo Nordisk, revised 05/2026
- 4Mounjaro (tirzepatide) US prescribing information, sections 4, 5.2, 5.8 and 6.1. Eli Lilly, revised 08/2026
- 5Wegovy FlexTouch, UK Summary of Product Characteristics, sections 4.4 and 4.8. eMC, updated 22 Sep 2026
- 6Mounjaro KwikPen, UK Summary of Product Characteristics, sections 4.4 and 4.8. eMC, updated 8 Sep 2026
- 7MHRA Drug Safety Update: GLP-1 receptor agonists and dual GLP-1/GIP receptor agonists: strengthened warnings on acute pancreatitis, including necrotising and fatal cases. 29 Jan 2026
This guide explains what labels and published studies say. It isn't medical advice and doesn't replace your prescriber or pharmacist.
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