The tablet figures
Section 5.3 of the US prescribing information, Acute Gallbladder Disease, says treatment with Wegovy® is linked to more frequent gallstones and gallbladder inflammation. For the tablet it reports one number, repeated in section 6.1 [1]. The European tablet information quotes the same trial and fills one gap [2], and the trial’s registry entry lists serious events one by one [4].
| Measure | Placebo tablets | Wegovy® tablets |
|---|---|---|
| Gallstones, US label sections 5.3 and 6.1 [1] | 1% | 2.5% |
| Gallstones, EU SmPC section 4.8 [2] | 1% | 2.5% (“common”) |
| Gallbladder inflammation (cholecystitis), EU SmPC section 4.8 [2] | 0% | 0% |
| Gallstones recorded as a serious adverse event, ClinicalTrials.gov [4] | 0 of 102 | 1 of 204 |
Who was in that trial
The tablet safety data come from Study 7, known as OASIS 4: a randomized, double-blind trial in which 204 adults with obesity, or with overweight plus at least one weight-related condition, took Wegovy® 25 mg tablets for as long as 64 weeks, followed by seven weeks off the drug. People with type 2 diabetes were not enrolled [1][3].
The registry entry describes the climb to 25 mg in four-week steps of 3 mg, 7 mg and 14 mg, which differs from the 1.5 mg, 4 mg and 9 mg steps in the current label [1][4]. The Rybelsus® and Ozempic® tablets label reports that, in healthy volunteers, 3, 7 and 14 mg of the older tablet gave exposure without clinically significant differences from 1.5, 4 and 9 mg of the newer one [5]. Either way, the gallstone figure reflects roughly a year on 25 mg in people without diabetes, and says nothing about groups the trial left out.
What the figures cannot tell you
The US label gives a rate for gallbladder inflammation only for the injection: 0.6% of adults on the injection against 0.2% on placebo [1]. Europe’s 0% for the tablet comes from about 300 people, so it shows that inflammation was not seen in that trial rather than that it cannot happen [2].
The injection trials reported gallstones in 1.6% on Wegovy® and 0.7% on placebo. Those numbers come from different studies with different people and durations, and the label cautions that trials run under widely varying conditions, which limits comparisons between them. Setting 2.5% beside 1.6% is not a head-to-head comparison of the two forms [1].
Neither document says when in treatment the gallbladder events occurred. Both link stomach upset to dose increases, but they give no such timing for gallstones [1][2].
Why stones may form
What the label supports: losing a lot of weight, or losing it quickly, raises the risk of gallstones. The label then adds that acute gallbladder disease was still more frequent on Wegovy® than on placebo even after adjusting for weight lost, so weight loss does not explain the whole difference [1].
What studies suggest but do not explain: a meta-analysis of 76 randomized trials with 103,371 participants found GLP-1 medicines associated with a higher risk of gallbladder or bile duct disease overall (relative risk 1.37), with a stronger association in weight-loss trials, at higher doses and with longer use. It measured association, not the mechanism behind it, and did not look at Wegovy® tablets separately [6].
General medical background: MedlinePlus lists rapid weight loss from a very low-calorie diet or after weight-loss surgery among factors that make gallstones more likely, alongside being overweight [7].
Other things that cause similar pain
Gallstones are common whatever the medicine. MedlinePlus says they are more frequent in women, in people over 40, in people with overweight or a family history, and with diabetes or birth control pills; many people with stones never have symptoms [7].
NIDDK notes that a gallbladder attack can look like appendicitis, a stomach ulcer, pancreatitis or reflux disease, all of which need a doctor’s assessment [8]. Within the Wegovy® label, upper abdominal pain also features in the pancreatitis warning: severe pain that persists, may reach the back and may come with nausea or vomiting [1].
If stones are suspected
For clinicians, section 5.3 says a suspicion of gallstones calls for gallbladder studies and clinical follow-up, so expect tests rather than a decision based on symptoms alone [1]. MedlinePlus describes ultrasound as a common way to see cholesterol stones, along with blood tests such as liver tests and pancreatic enzymes [7].
MedlinePlus adds that stones without symptoms usually do not need surgery, while people with symptoms often have the gallbladder removed, most often by keyhole surgery. The Medication Guide also notes that some gallbladder problems need surgery [1][7].
Symptoms worth a call
- Pain in the upper part of your stomach area [1].
- Fever [1].
- Yellowing of your skin or the whites of your eyes (jaundice) [1].
- Pale, clay-coloured stools [1].
- NIDDK adds that pain lasting several hours, nausea and vomiting, chills or tea-coloured urine during or after an attack need a doctor right away [8].
Wegovy®, Rybelsus® and Ozempic® are registered trademarks of Novo Nordisk A/S. PepLabo is not affiliated with or endorsed by Novo Nordisk.
When to get help
| Sign | Who to contact | How fast | Source |
|---|---|---|---|
| Severe stomach pain that will not go away, with or without vomiting, possibly reaching the back | Stop Wegovy® and call your healthcare provider right away | Emergency | Medication Guide [1] |
| Abdominal pain lasting several hours, or with fever, chills, jaundice, tea-coloured urine or pale stools | A doctor right away | Emergency | NIDDK [8] |
| Upper stomach pain, fever, yellowing of skin or eyes, or clay-coloured stools | Your healthcare provider | Today | Medication Guide [1] |
| Known gallstones before starting, or an earlier gallbladder attack | Your prescriber | At your next appointment | Section 5.3 [1] |
