Comparative pharmacokinetics of ceftazidime in young, healthy and elderly, acutely ill males

The pharmacokinetics of ceftazidime have been investigated after single and multiple i.v. doses in 9 young healthy male volunteers and 15 elderly male patients with acute bacterial infections. All subjects had normal, age-correlated glomerular function. Distribution and elimination in young volunteers were unaffected by posture and were similar to what has been reported earlier. In contrast, elderly patients had longer t1/2 beta (3.1 vs 1.9 h), larger AUC (414.0 vs 276.6 h.mg/l), lower total and renal clearances, reduced urinary recovery over 12 h and enlarged Vss. Total serum clearance of ceftazidime was closely correlated with the 51Cr-EDTA clearance. There was no significant change in 51Cr-EDTA clearance after seven days of treatment. A reduction in the dose of beta-lactam antibiotics eliminated by the kidney is advisable in elderly patients with an acute bacterial infection.