Is low-dose tadalafil better than tamsulosin? A randomized controlled trial in shockwave lithotripsy for solitary upper tract calculi.

OBJECTIVE: To ascertain whether low-dose tadalafil (5 mg) is more efficient than tamsulosin (0.4 mg) in facilitating calculus expulsion in those receiving extracorporeal shockwave lithotripsy for solitary upper urinary tract calculi. PATIENTS AND METHODS: This was a triple-blinded, prospective, superiority, randomized controlled, single-centre trial. A total of 250 patients with solitary renal or ureteric calculus measuring 6-24 mm were randomized (1:1) to receive either 0.4 mg tamsulosin or 5 mg tadalafil daily for 30 days or until calculus clearance, whichever was earlier. RESULTS: There was no difference in the primary outcome, namely, calculus expulsion rate at 30 days (tamsulosin vs tadalafil, n (%) 99 [81.1%] vs 98 [80.3%] respectively, 95% confidence interval = 0.8% [-9.0, 10.7], P = 0.874). Similarly, a lack of difference was also noted in the secondary outcome, number of days to expulsion (tamsulosin vs tadalafil, geometric mean [SD] 13.59 [2.39] vs 13.74 [2.39] respectively, P = 0.928). Four patients discontinued the drug due to adverse drug reactions in the tadalafil group. CONCLUSIONS: Low-dose tadalafil is not superior to tamsulosin in improving calculus expulsion when used as an adjunct to shockwave lithotripsy. In this study, we also noted that tadalafil was less tolerated.