Rate of Gallstone Dissolution with Actigall (Ursodiol)
Actigall (ursodiol) requires 1 to 2 years of daily treatment to achieve complete gallstone dissolution in appropriately selected patients, with approximately 30% of unselected patients achieving complete dissolution and up to 50-81% success in optimal candidates with small, cholesterol-rich stones. 1
Treatment Duration and Success Rates
Complete stone dissolution can be anticipated in about 30% of unselected patients with uncalcified gallstones < 20 mm in maximal diameter treated for up to 2 years at a dose of approximately 10 mg/kg/day 1
The dissolution rate is significantly higher (up to 81%) in patients with very small stones (≤ 5 mm in diameter) 1
For patients with floating or floatable stones (high cholesterol content), the chance of dissolution increases up to 50% 1
Treatment duration typically ranges from 6 months to 2 years, with most patients requiring 1-2 years for complete dissolution 1, 2
Factors Affecting Dissolution Speed
Stone size is inversely related to dissolution success: stones up to 5 mm dissolve in 81% of cases, while stones > 20 mm rarely dissolve 1
Partial stone dissolution within 6 months predicts a > 70% chance of eventual complete dissolution with continued therapy 1
Partial dissolution observed within 1 year indicates a 40% probability of complete dissolution 1
Stones < 6 mm in diameter are best treated with oral bile acids alone and may achieve up to 75% complete dissolution annually with careful patient selection 3
Patient Selection Criteria for Optimal Results
Gallstones must be radiolucent (cholesterol-rich) and uncalcified 1, 3
The cystic duct must be patent, as indicated by gallbladder opacification on oral cholecystography 3
Patients with calcified gallstones prior to treatment, or those who develop stone calcification during treatment, rarely dissolve their stones 1
Gallbladder non-visualization developing during ursodiol treatment predicts failure of complete stone dissolution, and therapy should be discontinued in such cases 1
Important Limitations and Caveats
Ursodiol is generally limited to gallstones with diameter less than 1.5 cm 4
Age, sex, weight, degree of obesity, and serum cholesterol level are not related to the chance of stone dissolution 1
Stone recurrence occurs in approximately 30-50% of patients within 2-5 years after complete dissolution 1, 3, 5
Serial ultrasonographic examinations should be obtained to monitor for stone recurrence 1
Comparison to Alternative Therapies
Oral bile acids must be taken daily for up to 2 years, and because of their limited efficacy, their use is not widespread 4
Extracorporeal shock-wave lithotripsy combined with ursodiol achieves stone-free status in 21% of patients at 6 months (versus 9% with lithotripsy alone), with higher success rates (35%) for solitary radiolucent stones < 20 mm 6
Surgical removal (cholecystectomy) offers immediate and permanent stone removal, prevents future pain, complications, and gallstone recurrence, and is not limited by stone size or composition 4
Clinical Algorithm for Treatment Duration
Begin ursodiol at 8-10 mg/kg/day for optimal dissolution 1
Perform ultrasonography at 6 months: if partial dissolution is present, continue therapy with > 70% chance of complete dissolution 1
If no dissolution at 6 months, consider alternative therapy 1
Continue treatment for up to 2 years for complete dissolution in responsive patients 1, 2
After dissolution, monitor with serial ultrasound for recurrence, which may occur in 30-50% of patients within 2-5 years 1, 3