ursodeoxycholic acid udca can be chemically synthesized. Ursodeoxycholic acid reduces cholesterol absorption and is used to dissolve (cholesterol) gallstones in patients who want an alternative to surgery. The drug is very expensive, however, and if the patient stops taking it, the gallstones tend to recur if the condition that gave rise to their formation does not change. For these reasons, Ursodeoxycholic acid has not supplanted surgical treatment by cholecystectomy.