Cholelithiasis

Cholelithiasis is the medical word for gallstones — hardened deposits that form in the gallbladder, the small organ that stores bile for digesting fat. Most gallstones cause nothing at all. When one blocks a duct, it produces sudden, severe pain under the right ribs, often after a fatty meal, sometimes with nausea, fever or yellowing of the skin. That is a same-day medical problem, not a wait-and-see one.

Every GLP-1 label in this category carries an Acute Gallbladder Disease warning, instructing clinicians to order gallbladder studies if cholelithiasis or cholecystitis is suspected. The risk is real and quantified: a 2022 meta-analysis of 76 randomized trials covering 103,371 patients found GLP-1 use associated with a 37% higher relative risk of gallbladder or biliary disease. The signal was stronger at higher doses, with longer use, and in trials run specifically for weight loss, where the relative risk reached 2.29.

The mechanism is partly the drug and partly the weight loss itself. Rapid weight reduction of any cause — dieting, surgery, medication — raises gallstone risk, because bile composition shifts and the gallbladder empties less often. Slowed gallbladder emptying from GLP-1 signaling likely adds to it.

The confusion worth correcting is treating this as a rare footnote. In STEP TEENS, 4% of adolescents on semaglutide developed gallstones over 68 weeks against none on placebo. It is uncommon, but it is not exotic, and it is the adverse event most likely to interrupt treatment with a hospital visit.

Tell your clinician about any prior gallbladder attack or a family history before starting, and ask what symptoms should send you to urgent care rather than a message portal. Losing weight more gradually may help. Our gallbladder evidence review and side-effect timeline set out when the risk peaks.