Background: Considering the medical applications of zinc oxide nanoparticles, evaluating their adverse effects on the organisms is important.

Materials and Methods: In this study, the effect of a single injection (ip) of zinc oxide nanoparticles (50, 100, 200, 300mg/kg) on changes in the renal parameters (uric acid, creatinin, urea) was studied after 8 and 30 days of the treatment.

Results: Results showed that the urea and creatinine levels in the 300 mg/kg group were significantly increased 8 days after the injection (P<0.001). The amount of uric acid reduced significantly in all the groups compared to the control group (P<0.001), while no significant difference was found between the groups 30 days after the injection.

Conclusion: It seems that a single injection of zinc oxide nanoparticles, especially at high doses (300 mg/kg), has a short-term effect (8 days) on the renal function, but after a month, possibly with the gradual elimination of nanoparticles uptake into the kidney, these effects disappear. However, further studies with more injections are essential.