The Wegovy label includes acute gallbladder disease as a warning, and SELECT/source data point to a small absolute increase in gallbladder-related events.

The mechanism is biliary chemistry: when body fat drops fast, cholesterol concentration in bile goes up, and slower gut motility lets gallstones form.

The same risk exists with bariatric surgery, very-low-calorie diets, and other rapid-weight-loss methods. GLP-1 medicines can contribute too. The practical way to understand it is this: gallbladder risk can rise for two reasons at once. The medicine changes digestion, and fast weight loss changes bile.