[Laboratory and clinical studies on ceftizoxime (author's transl)]

The authors have carried out the laboratory and clinical studies of ceftizoxime (CZX), and obtained the following results. 1. The antibacterial activities of CZX were measured by plate dilution method against clinical isolates of S. aureus, E. coli, K. pneumoniae and P. aeruginosa. CZX inhibited the growth of S. aureus at concentrations less than 12.5 micrograms/ml, and the peak of sensitivity distribution was obtained at 3.13 micrograms/ml with an inoculum size of 10(6) cells/ml. And the peak sensitivity distribution of E. coli and K. pneumoniae were obtained at less than 0.1 microgram/ml and that of P. aeruginosa was obtained at 6.25 micrograms/ml. 2. Phagocytosis was determined by Quie's method. Phagocytosis of E. coli and K. pneumoniae by human polymorphonuclear neutrophil was more enhanced in the presence of 1 MIC and 1/2 MIC of CZX than of CEZ at 4 and 6 hours after incubation. 3. As for pharmacokinetic study, CZX was given by intravenous injection and drip infusion for 1 hour at a single dose of 10 mg/kg and 30 mg/kg. After intravenous injection of 10 mg/kg and 30 mg/kg of CZX, the mean peak serum levels were 19.1 +/- 3.4 micrograms/ml and 69.1 micrograms/ml at 30 minutes, and half-life times were 1.20 hours and 1.35 hours, respectively. After 1 hour drip infusion of 10 mg/kg and 30 mg/kg of CZX, the mean peak serum levels were 28.8 +/- 3.6 micrograms/ml and 60.9 +/- 5.9 micrograms/ml at the end of infusion, and half-life times were 1.40 hours and 1.77 hours, respectively. The mean urinary excretion rates were between 75.3% and 101% up to 6 hours after intravenous injection and drip infusion. 4. CZX was given to 4 cases with tonsillitis, 3 with pneumonia, 1 with enteritis, 4 with U.T.I., totaling 21 cases. A daily dose of CZX between 350 mg and 2,000 mg was given for 3 to 5 days. Clinical results obtained were good in all cases. No side effects and abnormal laboratory findings were observed.