PHARMACOKINETICS OF CEFIXIME IN CHILDREN WITH URINARY-TRACT INFECTIONS AFTER A SINGLE ORAL DOSE

The pharmacokinetics of cefixime. a third-generation broad-spectrum ce phalosporin, were determined following administration of a 8 mg/kg sin gle oral dose of cefixime suspension to six children with urinary trac t infections, ages from 6 to 13 years and weights from 17 to 60 kg. Bl ood samples for determination of plasma cefixime concentrations were o btained for up to 12 hr and complete urine collections were obtained f or urinary excretion of unchanged parent drug for up to 24 hr after ad ministration. Plasma and urine concentrations of cefixime were determi ned using a reversed phase HPLC assay and pertinent pharmacokinetic pa rameters were estimated by model-independent standard methods. Mean pe ak plasma concentration was 4.04 mu g/ml and was reached after 3.2 hr. The mean area under the plasma concentration time curve was 33.07 mu g.hr/ml and the mean elimination half-life was 3.91 hr. The mean appar ent total clearance was 4.74 ml/min./kg and about 15% of the dose admi nistered was recovered unchanged in urine. In conclusion, the estimate d pharmacokinetic values of cefixime were comparable to those observed in healthy adult subjects based on equivalent mg/kg doses. Plasma and urine concentrations of the drug were well above the reported minimal plasma and urinary concentrations for most common urinary tract patho gens for up to 12 and 24 hr after administration, respectively.