Ursodiol reduces the size of common bile duct gallstones by wof mechanisms

GALLSTONE DISSOLVING DRUGS Cholesterol (CH) remains dissolved in bile with the help of bile salts (salts of cholic acid and chenodeoxycholic acid conjugated with glycine and taurine) because bile salts are highly amphiphilic. A high CH : bile salt ratio ours crystallization of CH in bile; these crystals act as nidi for stone formation. Chenodeoxycholic acid (Chenodiol) and Ursodeoxycholic acid (Ursodiol) decrease CH content of bile, enabling solubilization of CH from stone surface. Ursodiol:- It is a hydroxy epimer of chenodiol, is more effective and needs to be used at lower doses. Complete dissolution of CH stones has been achieved in upto 50% cases. It is also much better tolerated. Calcification of some gall stones may be induced. Ref:- kd tripathi; pg num:-671