Urdafalk contains ursodeoxycholic acid which suppresses hepatic synthesis and secretion of cholesterol and inhibits intestinal absorption of cholesterol. Ursodeoxycholic acid has little inhibitory effect on synthesis and secretion of endogenous bile acids, without affecting secretion of phospholipids into the bile.
Urdafalk converts cholesterol precipitates into readily soluble cholesterol by forming a lecithin cholesterol liquid layer on the surface of gallstones.