Cefotaxime dosage in infants and children. Pharmacokinetic and clinical rationale for an extended dosage interval.

Cefotaxime is a third generation cephalosporin antimicrobial agent which has received wide acceptance as a first-line antibiotic for many infections in neonates, infants and children. With an average elimination half-life of about 1 h, cefotaxime is not considered to be a 'long half-life cephalosporin' like ceftriaxone. For this reason, currently accepted dosage regimens for cefotaxime in infants and children employ a dosage of 50 mg/kg every 6 h. Re-examination of the paediatric pharmacokinetic data for cefotaxime and use of simple multiple-dose pharmacokinetic simulation of alternative dosage regimens was performed. From this analysis, regimens administering 75 mg/kg of the drug every 8 h or every 12 h were projected to produce serum cefotaxime concentrations adequate to effectively kill many of the common pathogens against which the drug is currently indicated for use in children. The clinical utility of these alternative dosage regimens was supported by a review of the medical literature and examination of the clinical results from studies in neonates, infants and children where cefotaxime was administered in 2 to 3 divided doses daily. It would appear, therefore, that increasing the cefotaxime dosage to 75 mg/kg administered at 8 h intervals would result in less frequent drug administration which would not be expected to compromise safety and efficacy. Alternative dosage regimens for cefotaxime merit further consideration and clinical evaluation before they become commonly used in paediatric therapeutics.