ursodiol

noun

ur·​so·​di·​ol ˌər-sō-ˈdī-ˌȯl  -ˌōl 

: a bile acid C₂₄H₄₀O₄ stereoisomeric with chenodeoxycholic acid that is taken orally to dissolve uncalcified radiolucent gallstones and to treat primary biliary cirrhosis

Oral dissolution therapy with ursodiol (ursodeoxycholic acid) administered orally for 6 to 12 months results in the dissolution of 60% to 90% of susceptible stones.

—Aijaz Ahmed et al., WebMD Scientific American Medicine

called also ursodeoxycholic acid