Adjuvant Tamsulosin or Nifedipine After Extracorporeal Shock Wave Lithotripsy for Renal Stones: a Double Blind, Randomized, Placebo-controlled Trial

OBJECTIVE To evaluate the effects of the adjuvant use of tamsulosin or nifedipine after extracorporeal shock wave lithotripsy for nonlower pole kidney stones 5-20 mm in size. METHODS We conducted a randomized double-blind trial involving 136 patients with radiopaque kidney stones. The patients received daily treatment with 0.4 mg tamsulosin, 20 mg nifedipine retard, or placebo for <= 30 days after 1 session of extracorporeal shock wave lithotripsy. Success was defined as plain film radiography showing the patient was completely stone free or with asymptomatic stone fragments <= 4 mm in size at any time during the weekly follow-up. RESULTS The success rate was 60.5% (23 of 38) in the tamsulosin group, 48.6% (17 of 35) in the nifedipine group, and 36.8% (14 of 38) in the placebo group (P = .118). In the subgroup analysis, stones 10-20 mm had significantly greater success rates in the tamsulosin (13 of 21, 61.9%) and nifedipine (15 of 25, 60%) groups compared with the placebo group (6 of 23, 26.1%; P = .024), but not for stones 5-9 mm (P = .128). The number needed to treat was 2.9 for tamsulosin and 3 for nifedipine. Adverse events were more frequent in the nifedipine than in the placebo group (28.5% vs 2.6%, respectively, P = .009), but without a significant difference between the nifedipine and tamsulosin (28.5% vs 15.8%, P = .15) or the tamsulosin and placebo (P = .54) groups. No difference was found among the groups with regard to pain intensity, interval to clearance, or steinstrasse. CONCLUSION The stone-free rates after extracorporeal shock wave lithotripsy with adjuvant tamsulosin or nifedipine were significantly increased only for nonlower pole renal stones 10-20 mm in size compared with placebo. Nifedipine was associated with more adverse effects than placebo. UROLOGY 78: 1016-1022, 2011. (C) 2011 Elsevier Inc.