Pharmacokinetics of Imipenem/Cilastatin Sodium in Children with Peritonitis

Abstract: Fifteen children (3-12 years) with peritonitis were given imipenem/cilastatin intravenously (15 or 25 mg/kg) every six hours for 3-14 days. One day during treatment days 2-8, multiple blood and urine samples were collected from each individual over a six hour dosing interval. Twelve children completed the study. The urinary recovery of imipenem and cilastatin averaged 50-70% of the administered dose. The plasma t_1/2 for imipenem averaged 55 min. while that for cilastatin was even more rapid (~ 38 min.). Little or no accumulation of either imipenem or cilastatin was observed for this regimen in this age group of paediatric patients. Steady state conditions prevailed within 2 days of initiation of therapy. The pharmacokinetics of imipenem and cilastatin in paediatric patients 3-12 years of age appear similar to those observed for adults.