Randomized controlled trial of the efficacy of isosorbide-SR addition to current treatment in medical expulsive therapy for ureteral calculi

It has been suggested that nitrates are potent smooth muscle relaxants that may reduce pain and facilitate ureteral stone passage; therefore it may be an option for medical expulsive therapy in ureteral stones. In a prospective randomized controlled clinical trial, we evaluated the efficacy of medical expulsive therapy with isosorbide-SR 40 mg in patients with ureteral stones (≤10 mm). The patients with ureteral stones in KUB or urinary tract ultrasonography were randomized to receive methylprednisolone plus celecoxib without (control group), and with isosorbide-SR 40 mg (treatment group) for 21 days. 66 patients [33(50%) in control, 33(50%) in treatment group] were entered randomly to our study. The stone expulsion rate was not significantly different between two groups (54.5 vs. 45.5%) (P = 0.497). The need for surgical procedures were more common in control group within 21 days (9.4 vs. 6.1%) and more common in treatment group after 21 days (33.3 vs. 21.9%) (P = 0.756).Patients in the treatment group experienced more intractable pain (27.3 vs. 6.1%), intractable vomiting (3 vs. 0%) (P = 0.046) and hospitalization (3 vs. 0%) (P = 0.314). Drug side effects including headache and dizziness were more common in treatment group (39.4 vs. 9.1%) (P = 0.004). In our study, the use of isosorbide-SR in treatment group did not improve the stone expulsion rate in patients with ureteral stones (≤10 mm) but developed more side effects. Then it may not an appropriate alternative for medical expulsive therapy. Of course, further trials are recommended.