Medical expulsive therapy for ureter stone using naftopidil: A multicenter, randomized, double-blind, and placebo-controlled trial

OBJECTIVES A prospective, multicenter, randomized, double-blind, placebo-controlled trial evaluated the effects of naftopidil 75 mg for medical expulsive therapy for a single ureter stone. MATERIALS AND METHODS Patients diagnosed with a ureter stone were prescribed aceclofenac 100 mg or a combined medication of tramadol 37.5 mg and acetaminophen 325 mg. Patients then randomly received either naftopidil 75 mg or placebo. Primary endpoint was the stone passage rate at 14 days after medication. RESULTS The 150 patients enrolled in 6 institutions randomly received either naftopidil (n = 75) or placebo (n = 75). The percentages of ureter stone passed spontaneously 14 days after medication was 60.9% in the naftopidil group and 53.3% in the placebo group. Stone-free rates and the total use of analgesics showed no significant differences between the two groups. Stone-free rates at 14 days after medication were decreased when maximal stone size was increased: 39.4% (≥ 5 mm), 15.5% (≥ 6 mm), and 7.0% (≥ 7 mm). CONCLUSIONS The use of naftopidil 75 mg once daily was not effective in increasing spontaneous stone passage rates or reducing analgesic use. The maximal stone size < 6 mm and the follow-up for two weeks would be appropriate for applying medical expulsive therapy to patients with a single ureter stone.