Medical Expulsive Therapy for Ureter Stone Using Naftopidil

Inclusion Criteria: * \>= 20 years * single 3 to 10 mm ureter stone (longest diameter) Exclusion Criteria: * Presence of multiple ureter stones * Renal insufficiency (serum Cr \> 1.4 mg/dL) * Febrile urinary tract infections(fever \> 38°C, evidence of urinary infection) * pregnancy or breast feeding * solitary kidney * hypersensitivity to naftopidil * current use of any alpha-blocker, calcium-channel blocker, corticosteroid (within 4 weeks) * moderate or severe cardiovascular or cerebrovascular disease * hepatic dysfunction (\>2 x normal upper limit) * significant active medical illness which in the opinion of the investigator would preclude protocol treatment * Genetic disorder such as Galactose intolerance, Lapp Lactase deficiency, Glucose-Galactose malabsorption