Pharmacokinetics of ceftizoxime in patients undergoing continuous ambulatory peritoneal dialysis

The pharmacokinetics of ceftizoxime were studied in 12 patients on continuous ambulatory peritoneal dialysis. After a 3-g intravenous dose, the steady-state volume of distribution was 0.23 +/- 0.05 liter kg-1, with an elimination half-life of 9.7 +/- 5.1 h. The peritoneal clearance of ceftizoxime (2.8 +/- 0.7 ml min-1) contributed modestly to the overall serum clearance of the drug (17.1 +/- 7.4 ml min-1) and was greater than the renal clearance (0.8 +/- 0.8 ml min-1). The peritoneal concentration rose to 91 +/- 29 micrograms ml-1 at 6 h, which was 0.61 +/- 0.17 of the serum concentration. A 3-g intravenous dose of ceftizoxime given every 48 h would result in adequate activity against most susceptible organisms, but more frequent dosing may be necessary for less susceptible organisms.