Background: To determine the effect of tamsulosin, as adjunctive medical therapy on the outcome of extracorporeal shock wave lithotripsy (ESWL) for solitary renal and ureteric calculi.Methods: From January 2017 onwards, a prospective, randomized controlled study was conducted in patients with solitary renal or ureteral calculus measuring less than 20 mm undergoing ESWL. The study group (n=62) received 0.4 mg of tamsulosin daily till stone clearance or a maximum period of 12 weeks and control group (n=58) received ESWL only. Parameters assessed were stone size, composition, location, stone clearance, mean time to clearance, analgesic requirement, steinstrasse, need for hospitalization and/or auxiliary procedures.Results: There was no difference between the 2 groups with regards to age, stone size, location or composition. The complete clearance rate for renal stones was 62.7% and 36.5% (p=0.004) and for ureteric stone was 89.4% and 58.8% (p=0.03) in study and control groups, respectively. The control group had a higher rate of clinically insignificant residual fragments (CISF i.e. <3 mm), 12.9% versus 35.4% (p=0.002). There was no significant difference in the mean time to stone clearance (p=0.07) or in the incidence of steinstrasse formation (p=0.12). The mean analgesic requirement (p=0.01), need for auxiliary procedures and hospitalization (p=0.03) was significantly was higher in the control group.Conclusions: Tamsulosin increase the complete clearance rate and decrease the incidence of CISF. It also reduces analgesic requirement, need of additional procedures and hospitalization rate and might be useful as a routine adjunctive therapy following ESWL.