The Effect of Naftopidil for the Double-J Stent Discomfort

Inclusion Criteria:Patients to be undergone double-J stent indwelling * \>= 20 years * undergoing unilateral retrograde double J (DJ) stent placement planned for 5-15 days indwelling Exclusion Criteria: * after percutaneous nephrolithotomy, open or laparoscopic ureterolithotomy presence of ureteral stone * renal insufficiency (serum Cr \> 1.4) * febrile urinary tract infection (fever \> 38.0°C, evidence of urinary infection ) * pregnancy or breast feeding * solitary kidney * hypersensitivity to Naftopidil * current use of any alpha blocker, calcium channel blocker, corticosteroid moderate or sever cardiovascular or cerebrovascular disease * hepatic dysfunction * prior history of pelvic surgery or irradiation * prior history of transurethral resection of bladder tumor or prostate surgery * significant active medical illness which in the opinion of the investigator would preclude protocol treatment * genetic disorder such ad galactose intolerance, lapp lactase deficiency, glucose-galactose malabsorption