Potential nephrotoxicity of ceftezole (CTZ) and cefazolin (CEZ) was studied in rabbits by intravenous injections.
A single injection of 125, 250, 500 and 1000 mg/kg of CTZ or CEZ caused a dose-related renal injury. This was confirmed by the results of tests of clearance (PAH), PSP excretion, BUN and protein and sugar in urine, and also by macro-and micro-scopic examination of kidneys. CTZ or CEZ injection of 500 and 1000 mg/kg resulted in alteration of renal functions and caused a necrosis of proximal tubules, while 125 and 250 mg/kg administrations did not cause a renal injury.
In rabbits injected CTZ or CEZ, twice daily for 7 consecutive days at a dose of 64 and 125 mg/kg, no abnormalities were observed to be attributable to the drug treatment in both renal functions and kidney structure.
CTZ or CEZ injections at doses of 50 and 100 mg/kg/day for 21 consecutive days would have been not caused a renal injury, while 200 mg/kg dose caused a slight alteration in renal functions, and CTZ injection at doses of 200 mg/kg/day caused slight necrosis to the least extent in proximal tubules.
CTZ seemed to have much less nephrotoxic potential than CEZ.
