Pharmacokinetics of cefadroxil in normal subjects and in patients with renal insufficiency.

Pharmacokinetics of cefadroxil, a new orally semisynthetic cephalosporin, was studied in 5 subjects with normal renal function and in 20 patients with varying degrees of renal insufficiency. All subjects received 1,000 mg per os in a single dose and the elimination phase was studied. In healthy subjects, elimination half-life (T1/2) was 1.39 +/- 0.06 h. Apparent volume of distribution was 0.305 liters/kg and area under the serum concentration versus time curve AUC was 82.94 +/- 19.98 microgram . h/ml. Peak level averaged 25.72 +/- 4.68 microgram . ml-1 and occurred at 1.20 +/- 0.45 h postingestion. 93.0 +/- 3.6% of the dose was recovered in urine during the first 24 h. Renal and serum clearance averaged 166.7 and 172.4 ml . min-1/1.73 m2, respectively. In patients with renal insufficiency, T1/2 increased to 25.49 h in severe chronic renal failure. Renal impairment did not significantly modify volume of distribution. During a 6- to 8-hour hemodialysis session, antibiotic serum concentrations decreased by 75.4 +/- 5.6%. Dosage schedules could be suggested on the basis of these pharmacokinetic results.