[Pharmacokinetic studies on ceftazidime in neonates].

The pharmacokinetics of ceftazidime (CAZ) were investigated in neonates. The following was a summary of the results obtained. Mean peak serum levels of CAZ reached at 15 minutes after intravenous administrations at single doses of 10 mg/kg were 31.7 micrograms/ml in 1-day-old neonates and 31.4 micrograms/ml in a 13-day-old neonate. Mean serum levels at 6 hours after administrations were 8.97 micrograms/ml and 5.26 micrograms/ml in the 1-day-old and the 13-day-old, respectively. Mean half-lives of CAZ in sera were 3.29 hours in the 1-day-old and 2.24 hours in the 13-day-old. In a 4-day-old neonate, the serum level of CAZ reached a peak of 25.4 micrograms/ml at 1 hour and was 5.75 micrograms/ml at 6 hours; the half-life was 2.41 hours. Peak serum levels of CAZ reached at 15 minutes after intravenous administrations at single doses of 20 mg/kg were 46.3 micrograms/ml in a 3-day-old neonate and 80.6 micrograms/ml in a 7-day-old neonate. The serum levels at 6 hours after administration were 12.2 micrograms/ml and 10.4 micrograms/ml, in the 3-day-old and the 7-day-old, respectively. Half-lives of CAZ in sera were 3.02 hours in the 3-day-old and 2.08 hours in the 7-day-old. In 4-day-old neonates, mean serum levels were 52.5 micrograms/ml at 15 minutes and 14.6 micrograms/ml at 6 hours after administration and the half-life was 2.76 hours.(ABSTRACT TRUNCATED AT 250 WORDS)