Related Experiment Videos
Pharmacokinetics of intravenously administered piperacillin in preadolescent children
Insights
This study analyzed piperacillin pharmacokinetics in preadolescent children. Dosing of 50 mg/kg IV every four hours achieved adequate plasma concentrations for treating common infections.
Area of Science:
- Pharmacology
- Pediatric Medicine
- Drug Metabolism
Background:
- Piperacillin is a widely used antibiotic.
- Understanding its pharmacokinetics in children is crucial for effective dosing.
- Previous studies on pediatric piperacillin pharmacokinetics are limited.
Purpose of the Study:
- To determine the pharmacokinetic profile of piperacillin in preadolescent children.
- To assess the impact of age on piperacillin pharmacokinetics.
- To evaluate the adequacy of standard dosing regimens.
Main Methods:
- A pharmacokinetic study involving 37 preadolescent children.
- Intravenous administration of piperacillin at 50 mg/kg.
- Analysis of plasma piperacillin concentrations, elimination rate constants, half-lives, clearances, and volume of distribution.
Main Results:
- No significant differences in pharmacokinetic parameters between initial and subsequent doses.
- Mean plasma concentration at end of infusion: 166.2 mg/L; mean half-life: 31.0 minutes.
- Significantly longer half-life and lower clearance in infants (1-6 months) compared to older children.
- Nonrenal elimination accounted for a substantial portion of total body clearance.
Conclusions:
- Standard intravenous piperacillin dosing (50 mg/kg every 4 hours) provides adequate therapeutic concentrations in preadolescent children.
- Age-dependent pharmacokinetic differences exist, particularly in younger infants, necessitating potential dose adjustments.
- Nonrenal excretion plays a significant role in piperacillin elimination in this population.
Abstract:
We studied the pharmacokinetics of piperacillin in 37 preadolescent children (mean age 52 months, range 1 month to 11 years) after 50 mg/kg IV doses. Pharmacokinetic parameters were determined after the initial dose in 18 instances and after subsequent doses in 32 instances. There were no significant differences between the initial doses and the subsequent doses in the plasma piperacillin concentrations at comparable times, the elimination rate constants, the elimination-phase plasma half-lives, the total body clearances, the apparent volumes of distribution, or the areas under the concentration curves. At the end of a 30-minute infusion of the drug, the plasma concentration was 166.2 +/- 42.2 mg/L (mean +/- SD) and ranged from 91.6 to 268.3 mg/L. The mean half-life was 31.0 +/- 9.4 minutes. The half-life of piperacillin in children 1 to 6 months of age (47.2 minutes) was significantly longer than in older children (28.8 minutes) (P less than 0.05). Likewise, the total body clearance of the drug in the younger age group (71.7 ml/min/m2) was significantly lower than in the older children (130.8 ml/min/m2) (P less than 0.05). The mean renal clearance of the drug was only 63% (range 39% to 85%) of the total body clearance, suggesting a variable but substantial nonrenal route of elimination. The intravenous administration of 50 mg/kg piperacillin every four hours results in adequate plasma concentrations for the treatment of most infections caused by gram-negative and gram-positive organisms.