Ursodeoxycholic acid (UDCA) is a naturally occurring, hydrophilic, non-toxic bile acid utilized to protect hepatic and biliary systems. It functions by displacing toxic, hydrophobic endogenous bile acids from the circulating bile pool, reducing cell damage in the biliary epithelium. Furthermore, it suppresses hepatic cholesterol synthesis and secretion into bile, decreasing overall biliary cholesterol saturation. This allows for the gradual, step-by-step physical dissolution of radiolucent cholesterol gallstones while improving bile flow dynamics through the liver.