Ursodeoxycholic acid, originally in the form of bear bile, has been used to treat abdominal complaints in China and Japan for centuries. Its use was rediscovered in the West 10 years ago after the serendipitous finding that it not only dissolved cholesterol gall stones but greatly improved the liver function values of patients who had chronic liver disease.1 This finding resulted in a flurry of research, particularly into the use of ursodeoxycholic acid in primary biliary cirrhosis.

The results of four large, well designed, double blind, placebo controlled trials are now available.*RF 2-5* All studied patients for two years and reported broadly similar results - that ursodeoxycholic acid greatly improves serum concentrations of bilirubin and liver enzymes. Serum bilirubin concentration of untreated patients with primary biliary cirrhosis is an independent predictor of outcome. Alkaline phosphatase and (gamma)-glutamyl transpeptidase values reflect cholestasis, and serum transaminase values indicate the degree of hepatocellular damage.

Although these results are encouraging, their long term importance is unclear. In particular, …