Independent UK medicine guidance
Mounjaro and gallstones: symptoms and warning signs
Gallstones are listed as a common Mounjaro side effect when tirzepatide is used for weight management. Inflammation or infection of the gallbladder, known as cholecystitis, is listed as uncommon. This guide explains what gallbladder pain feels like and when it becomes an emergency.
How common is it?
The events were positively correlated with weight reduction. This means the risk may be connected partly to losing weight, particularly rapid weight loss, rather than being a simple direct effect of the medicine.
What do gallstones feel like?
Gallstones often cause no symptoms. When a stone blocks a bile duct, symptoms can include:
- Constant or severe pain in the upper abdomen
- Pain under the ribs on the right
- Pain spreading to the back or right shoulder
- Nausea or vomiting
- Pain lasting longer than 30 minutes
This is different from the brief discomfort, wind or mild stomach upset commonly experienced during treatment.
When is it an emergency?
Contact NHS 111 urgently if abdominal pain lasts longer than 30 minutes.
Call 999 or attend A&E for sudden severe abdominal pain, particularly if it is accompanied by repeated vomiting, pain spreading into the back, a high temperature or shivering, yellowing of the skin or whites of the eyes, or confusion, collapse or severe weakness.
Severe persistent pain spreading to the back can also indicate pancreatitis, another serious condition requiring immediate assessment.
Read the full guide to pancreatitis warning signs
Can gallstones be prevented?
There is no guaranteed prevention method. Avoiding crash dieting and excessively rapid weight loss may reduce risk. A balanced diet, sustainable rate of weight loss and appropriate hydration are sensible foundations.
Tell your prescriber if you have previously had gallstones, gallbladder inflammation or pancreatitis. New abdominal pain should be assessed rather than dismissed as an ordinary Mounjaro side effect.
Common questions
Does Mounjaro cause gallstones?
Gallstones are listed as a common side effect of Mounjaro when used for weight management. In pooled SURMOUNT studies, acute gallbladder disease was reported in 2% of participants taking tirzepatide and 1.6% taking placebo, and the events were positively correlated with the amount of weight reduced. The risk may therefore be connected partly to weight loss itself rather than being a simple direct effect of the medicine.
What does gallbladder pain feel like?
When a stone blocks a bile duct, pain is often constant or severe in the upper abdomen, may sit under the ribs on the right, can spread to the back or right shoulder, may come with nausea or vomiting, and can last longer than 30 minutes. That is different from brief wind or mild stomach upset.
When should I get urgent help for abdominal pain?
Contact NHS 111 urgently if abdominal pain lasts longer than 30 minutes. Call 999 or attend A&E for sudden severe abdominal pain, especially with repeated vomiting, pain spreading into the back, a high temperature or shivering, yellowing of the skin or eyes, or confusion, collapse or severe weakness.
Related guides
Sources: Mounjaro Summary of Product Characteristics (eMC) • NHS gallstones guidance
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