Gallstones on GLP-1 medicines: why the risk rises and how to protect yourself

Losing weight quickly raises the risk of gallstones forming in the gallbladder. The official product information for GLP-1 medicines also lists gallbladder problems as a known risk. Regular meals, a little healthy fat in meals, fiber-rich foods, enough water and a steady pace of weight loss help lower the risk. Some symptoms mean you should see a doctor without waiting.

What does the gallbladder do?

The gallbladder stores bile, which the liver makes. When you eat, especially when a meal contains some fat, it contracts and empties bile into the intestine. If bile sits in the gallbladder for a long time, the cholesterol in it can settle out and form stones.

Why does the risk go up?

• Rapid weight loss: When weight comes off quickly, the liver releases more cholesterol into bile.
• Skipping meals: When your appetite drops, it becomes easy to skip meals. Without food, the gallbladder does not contract and bile sits inside it.
• Too little fat: Meals with no fat at all make the gallbladder empty less. In a small study of very-low-calorie diets, more than half of the participants on the diet with very little fat developed stones; none did on the diet with a little more fat.
• The medicine itself: In an analysis that pooled randomized trials, gallbladder and bile duct diseases were more common with GLP-1 medicines than with placebo or other medicines. The increase was clearer with use for weight loss and with longer use; the absolute risk stayed small.

Who is at higher risk?

Women, people over 40, people with a family history of gallstones, people who have had gallstones before, and people who lose weight very quickly.

How can you protect yourself?

• Don't skip meals. Even when your appetite is low, eat small meals at regular times through the day.
• Include a little healthy fat in your meals: olive oil, walnuts, hazelnuts, almonds or avocado, for example. Don't cut out fat completely.
• Eat more fiber: vegetables, fruit, beans, lentils and whole grains.
• Drink water regularly through the day. These medicines can cause constipation, nausea or vomiting; enough fluid matters for both your bowels and your kidneys. For most adults, about 1.5–2 liters (about 6–8 cups) a day from water and other drinks is enough; you need more in hot weather and on active days. If you have heart or kidney disease, ask your doctor how much to drink.
• Lose weight at a steady pace. About 0.5 to 1 kg (roughly 1 to 2 lb) a week is generally considered safer. If you are losing much faster than that, talk to your doctor.
• Stay active. Regular physical activity is associated with a lower risk of gallstones.
• If your risk is high, your doctor may suggest a preventive medicine; that decision belongs to your doctor.

Don't wait with these symptoms

If any of the following happens, see a doctor or go to the emergency department the same day, and say that you take a GLP-1 medicine:

• Pain in the upper right or upper middle part of your abdomen that lasts a few hours or keeps getting worse; it may spread to your right shoulder or back and often starts after a meal.
• Fever or chills.
• Yellowing of the eyes or skin, dark urine, pale stools.
• Severe abdominal pain that spreads to your back and does not go away, with vomiting; this can be a sign of pancreatitis (inflammation of the pancreas).

Questions to ask your doctor

• Is my risk of gallstones high? Do I need an ultrasound before I start?
• What should I do if I lose weight very quickly?
• Do I need a preventive medicine?

Sources

• FDA-approved prescribing information, Warnings, acute gallbladder disease: semaglutide · tirzepatide
• He L, et al. Association of Glucagon-Like Peptide-1 Receptor Agonist Use With Risk of Gallbladder and Biliary Diseases: A Systematic Review and Meta-analysis of Randomized Clinical Trials. JAMA Intern Med. 2022;182(5):513–519.
• Festi D, et al. Gallbladder motility and gallstone formation in obese patients following very low calorie diets. Use it (fat) to lose it (well). Int J Obes. 1998.
• NIDDK (US National Institutes of Health), gallstones: symptoms and causes · eating, diet and nutrition
• EFSA (European Food Safety Authority). Scientific Opinion on Dietary Reference Values for water. EFSA Journal. 2010;8(3):1459.

Related: GLP-1 medicines: frequently asked questions

Medical content review: Prof. Dr. Varlık Erol, Professor of General Surgery · Gila advisor. He reviewed the Turkish original; this English version is Gila's translation.

Last updated: November 1, 2026 · Editor: Sezen Soykut · support@gila.coach

This page is for information only and is not medical advice. Make decisions with your doctor.