A prospective, double-blind, randomized, single-center study was conducted to compare
ursodeoxycholic acid alone with the combination of
ursodeoxycholic acid and
chenodeoxycholic acid for dissolution
therapy of
gallstone fragments after
shock wave
lithotripsy. Patients with single radiolucent
gallstones up to 30 mm in diameter or up to three stones of similar total volume received either 750 mg
ursodeoxycholic acid alone (group A, n = 138) or the combination of 500 mg
ursodeoxycholic acid and 500 mg
chenodeoxycholic acid (group B, n = 144) in a single bedtime dose. The
bile acids were administered from 2 wk before electrohydraulic
lithotripsy until 3 mo beyond complete disappearance of all fragments. Patient's characteristics, stones (group A, 82% single stones, maximum diameter 19 +/- 5 mm, mean +/- S.D.; group B, 82% single stones, 18 +/- 5 mm),
lithotripsy treatment and follow-up period were not different between the two groups. Between the two groups, no statistically significant difference was found in the time required for complete clearance of the fragments (group A, median time = 15 mo; group B, median time = 13 mo; p = 0.7). At 12 mo after
lithotripsy, the probability of complete clearance was 46% +/- 5% in group A and 49% +/- 5% in group B.
Diarrhea occurred significantly more often in group B than in group A (p less than 0.001) and was the main reason for withdrawal of randomized medication. Severe adverse effects of the
bile acids were not observed. It is concluded that monotherapy with
ursodeoxycholic acid is as efficient as the combination of
ursodeoxycholic acid and
chenodeoxycholic acid for fragment dissolution after
lithotripsy.(ABSTRACT TRUNCATED AT 250 WORDS)