Penetration of cefazolin and methicillin into tissues of rats with aseptic inflammation

Penetration of cefazolin and methicillin into the tissues of rats with aseptic inflammation was studied. Free cefazolin was shown to be present in blood serum and tissues in higher concentrations than methicillin. The level of cefazolin penetration in all the tested tissues was higher than that of methicillin. Elimination of the antibiotic from the focus of the aseptic inflammation was markedly retarded as compared to that from blood serum. It was suggested that the tissue binding of the antibiotics influenced the rate of their elimination from the tissues.