Cephalexin: human studies of absorption and excretion of a new cephalosporin antibiotic

Abstract

. Serum levels, half‐lives and urine concentrations of cephalexin, an oral cephalosporin antibiotic which is unique in its absorption and excretion, are reported in human volunteers, fasting, non‐fasting and non‐fasting plus probenecid. Accumulation does not seem to occur. . Cephalexin clearance was 376 ml./min and the ratio of cephalexin/creatinine clearances was 2·6 in one volunteer. . Cephalexin had no effect on the urinary excretion of leucocytes, red cells or protein. . The very high rate of absorption giving high serum levels and urine concentrations suggest cephalexin will be a useful antibiotic in susceptible bacterial infections in man.

Tissue Distribution of Cephalexin in Pregnant Rabbit and Fetus after Oral and Intramuscular Administration

“…In accord with many clinical and laboratory investigations [5][6][7], our results indicate that this antibiotic is rapidly absorbed when given by oral route in the rabbit.…”

Effects of cephalexin, erythromycin and clindamycin on the aerobic gram-negative faecal flora in man (Plate VII)

“…The concentration of cephalexin excreted in the faeces appeared to reach levels sufficiently high to influence the aerobic intestinal flora, contrary to the expectation of Gower and Dash (1969). The cephalexin concentration in the faeces of the subjects (3-6 pg per g) exceeded the MIC for the majority of intestinal strains of E. coli.…”

The Susceptibility of <i>Clostridium perfringens</i>Type A to Cephalosporin C Antibiotics <i>in vitro</i>

“…It was of interest to note that 4 strains required higher concentrations of cephalexin and cephaloglycin (12 g/ml) for inhibition and/or killing than did the majority of the isolates. However, blood levels of this magnitude can be achieved with ordinary dosage of any of these cephalosporins [2,3,4,6,7,9,11,14]. A disturbing finding was the lack of agreement between the 2 dilution methods with regard to cephalexin.…”