ursodiol

Ursodiol, also known as ursodeoxycholic acid and the abbreviation UDCA, is one of the secondary bile acids, which are metabolic byproducts of intestinal bacteria. Primary bile acids are produced by the liver and stored in the gall bladder. When secreted into the colon, primary bile acids can be metabolized into secondary bile acids by intestinal bacteria. Primary and secondary bile acids help the body digest fats. Ursodeoxycholic acid helps regulate cholesterol by reducing the rate at which the intestine absorbs cholesterol molecules while breaking up micelles containing cholesterol. Because of this property, ursodeoxycholic acid is used to treat (cholesterol) gallstones non-surgically.
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Ursodiol /ur·so·di·ol/ the secondary bile acid ursodeoxycholic acid used as an anticholelithic to dissolve radiolucent, noncalcified gallstones. [more]Ursodiol - Community and Resources

[ur-so-DYE-ole]
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.