A drug that is used to dissolve gallstones in people who can't have surgery to remove them. It is also being studied in the prevention of colorectal cancer. Ursodiol belongs to the family of drugs called anticholelithics.

A synthetically-derived form of ursodiol, a bile acid produced by the liver and secreted and stored in the gallbladder. Also produced by the Chinese black bear liver, ursodiol has been used in the treatment of liver disease for centuries. This agent dissolves or prevents cholesterol gallstones by blocking hepatic cholesterol production and decreasing bile cholesterol. Ursodiol also reduces the absorption of cholesterol from the intestinal tract.

(ursodeoxycholic acid) An epimer of chenodeoxycholic acid. It is a mammalian bile acid found first in the bear and is apparently either a precursor or a product of chenodeoxycholate. Its administration changes the composition of bile and may dissolve gallstones. It is used as a cholagogue and choleretic.