Background: Aminoglycosides are frequently used in children and adult s . Depending on the patient's age and the nature of the disease, the standard dose of aminoglycosides is 2-3 times daily. The aim of the present research was to compare the side effects and the efficacy of gentamycin administered in single and divided doses. This study was carried out on urinary tract infections of patients hospitalized in Paediatrics and Infectious wards of Kashan Shahid Beheshti Hospital.

Materials and Methods: This clinical trial study was carried out on 30 patients. The patients were randomly divided equally into two groups (n=15). The case and control groups were treated with single and multiple daily divided doses of gentamycin (total daily doses of 3 mg/kg/day), respectively. The daily data of fever, dysuria, urinary frequency and the laboratory findings were recorded for the comparison of safety and efficacy of the two methods. The nephrotoxicity of the drug was evaluated through the creatinine level.

Results: The patients were in an age range of newborn to 15 years with a male/female ratio of 5/6. The average period for the recovery of signs (disappreance of dysuria and urinary frequency) in the gentamycin and control groups was 1.6 and 2.06 days, respectively (P = 0.127). The average duration for the elimination of fever in the case and control groups was 1.4 and 1.8 days, respectively. The average level of creatinine (final day compared to the first day) betwen the two groups was equal.

Conclusion: The rate of treatment in both groups was similar with no more nephrotoxicity in single–dose. For routine single-dose administration of gentamycin, more research in broader age ranges is suggested.