Purpose: To compare the effects of tadalafi l, tamsulosin, and placebo as a medical expulsive therapy (MET) for distal ureteral calculi. Materials and Methods: This prospective randomized double-blind clinical trial was conducted on 132 renal colic patients with distal ureteric stones (≤10mm) over a period of 12 months. Patients were randomly divided into three groups. Patients in group A received tamsulosin 0.4mg, in group B received tadalafi l 10mg, and in group C received placebo. Therapy was given for a maximum of 4 weeks. The rate of stone expulsion, duration of stone expulsion, the dose and the duration of nonsteroidal anti-infl ammatory drugs (NSAIDs), analgesic use, and adverse effects of drugs were recorded. Results: Demographic profi les were comparable between the 3 groups. Although the stone expulsion rate in group A (72.7%) was higher in comparison to group B(63.6%) and group C(56.8%), it was not considered statistically signifi cant (P=0.294). Shorter mean time to stone expulsion was signifi cantly observed in group A (17.75±75), than group B(21.13±1.17) and group C(22.25±1.18) (P=0.47). The mean number of analgesic use was 9.8±5.09 days in group A, 14.6±7.9 days in group B, and 12.6±22.25 days in group C, this difference was signifi cant (P=0.004). The analgesic requirement (doses of NSAIDs and pethidine) in group A was signifi cantly lower than other groups (P<0.05). Also, patients in group A reported fewer headaches compared to other groups (P=0.011). Conclusion: Tamsulosin as medical expulsive therapy is more effective for distal ureteric stones with less need for analgesics and less stone expulsion time than tadalafi l.