Susceptibility of Neisseria gonorrhoeae to ceftizoxime in vitro and in vivo.

Ceftizoxime - a new beta-lactamase-resistant cephalosporin - was tested for its potential efficacy in the cure of uncomplicated gonorrhea. While more than a half of the 102 freshly isolated Neisseria gonorrhoeae strains examined was partially or totally resistant to penicillin (MIC greater than or equal to 0.06 microgram/ml), most of these strains proved highly susceptible to ceftizoxime (as well as cefotaxime). The MIC90% amounted to 0.004 micrograms/ml, while serum levels after the intramuscular application of as little as 0.5 g exceed 1 microgram/ml for more than 6 h. The clinical results were excellent. 105 male or female patients suffering from uncomplicated gonorrhea were treated with a single intramuscular application of 1 g of ceftizoxime. 61 of them reattended our clinic twice for follow-up. All of them were cured. Anaphylactic shock or rashes were not observed. Thus, we consider the intramuscular application of 1 g of ceftizoxime as a reliable and safe treatment for uncomplicated gonococcal urethritis and cervicitis.