Cefatrizine (SK&F 60771), a new oral cephalosporin: serum levels and urinary recovery in humans after oral or intramuscular administration--comparative study with cephalexin and cefazolin.

Cefatrizine (SK&F 60771), a new broad-spectrum cephalosporin, was administered in a 0.5-g dose either orally or intramuscularly to volunteers in a crossover study. After oral administration, the average peak serum levels were 5.6 and 22.1 mug/ml for cefatrizine and cephalexin, respectively. The serum half-life of cefatrizine appeared to be more extended than that of cephalexin. Urinary recovery of cefatrizine (35%) was approximately half that of cephalexin (68%) after oral administration. After intramuscular injection of 0.5 g, the average peak serum level of cefatrizine (12.0 mug/ml) was approximately one-fourth that of cefazolin (44.0 mug/ml). The serum half-life after intramuscular injection was 86 min for cefatrizine and 118 min for cefazolin. Urinary recovery was 45% of the intramuscularly administered dose, as compared with cefazolin, which was 74%.