Background: The radiation sterilization is one of the best methods for sterilizing vulnerable for degradation drugs like cefozopran hydrochloride.

Results: Chemical stability of radiosterylized cefozopran hydrochloride, was confirmed by spectrophotometric and chromatographic methods. EPR studies showed that radiation has created some radical defects which concentration was no more than several dozen ppm. The antibacterial activity of cefozopran hydrochloride irradiated with a dose of 25 kGy was unaltered for Gram-positive bacteria but changed for two Gram-negative strains. The radiation sterilized cefozopran hydrochloride was not in vitro cytotoxic against human CCD39Lu normal lung fibroblast cell line.