Treatment Options for Dissolving Gallstones
For patients with cholesterol gallstones in a functioning gallbladder, ursodeoxycholic acid (UDCA) at a dose of 8-10 mg/kg/day is the recommended medical therapy for stone dissolution, though it has limited efficacy and is only appropriate for select patients with small (<1.5 cm) radiolucent cholesterol stones. 1, 2
Patient Selection for Medical Dissolution Therapy
Medical dissolution therapy with UDCA is appropriate only for patients who meet specific criteria:
- Confirmed cholesterol gallstones (radiolucent on imaging)
- Stone diameter less than 1.5 cm
- Functioning gallbladder confirmed by oral cholecystogram
- No gallstone calcification
- No complications of gallstone disease
Factors Affecting Success Rates
- Stone size: Complete dissolution rates are highest (up to 81%) for stones smaller than 5 mm 2
- Stone composition: Only works for cholesterol stones (not pigment or calcified stones)
- Stone number: Fewer stones have better dissolution rates
- Patient characteristics: Not affected by age, sex, weight, or serum cholesterol levels 2
Medication Protocol
- Recommended agent: Ursodeoxycholic acid (UDCA)
- Dosage: 8-10 mg/kg/day 1, 2
- Duration: Treatment typically requires 6-24 months
- Monitoring: Serial ultrasonography every 3-6 months to assess dissolution progress
UDCA works by:
- Suppressing hepatic synthesis and secretion of cholesterol
- Inhibiting intestinal absorption of cholesterol
- Solubilizing cholesterol in micelles
- Dispersing cholesterol as liquid crystals in aqueous media 2
Efficacy and Limitations
- Complete dissolution occurs in approximately 30% of unselected patients with uncalcified gallstones <20 mm treated for up to 2 years 2
- Partial dissolution within 6 months predicts a >70% chance of eventual complete dissolution 2
- Stone recurrence after successful dissolution occurs in up to 50% of patients within 5 years 2, 3
Common Pitfalls and Limitations
- Calcified gallstones or stones >20 mm rarely dissolve 2
- Development of gallbladder nonvisualization during treatment predicts failure and therapy should be discontinued 2
- Acquired surface calcification during treatment (occurs in about 22% of patients) prevents successful dissolution 3
- UDCA is ineffective for non-cholesterol stones, such as those in cystic fibrosis patients 4
Alternative Approaches
While medical dissolution therapy has been studied, the American College of Physicians guidelines note that:
- Laparoscopic cholecystectomy is the definitive treatment for symptomatic gallstones 1, 5
- Cholecystectomy prevents future pain, complications, gallstone recurrence, and gallbladder cancer 1
- Other historical approaches like methyl-tert-butyl-ether (contact solvent) and extracorporeal shock-wave lithotripsy combined with oral bile acids have limited applications and remain largely investigational 1
Follow-up and Monitoring
- Monitor for stone dissolution with ultrasonography every 3-6 months
- Continue therapy if partial dissolution is observed within 6-12 months
- Discontinue therapy if:
- No dissolution is observed after 6-12 months
- Gallbladder becomes non-visualizing
- Stone calcification develops
- Severe biliary symptoms occur 3
Remember that even after complete dissolution, recurrence rates are high (30-50% within 2-5 years), so patients should be monitored with serial ultrasonography 2, 3.