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Determination of theophylline clearance in South African children

J H Botha1, I Tyrannes, R Miller

  • 1Department of Pharmacology, University of Natal, Durban, South Africa.

European Journal of Clinical Pharmacology
|January 1, 1993
PubMed

Insights

Theophylline clearance in South African children is influenced by age, gender, and weight. Clearance decreases with age, with specific values provided for different age groups, aiding in pediatric asthma management.

Area of Science:

  • Pharmacokinetics
  • Pediatric Pharmacology

Background:

  • Theophylline is a bronchodilator used in managing pediatric respiratory conditions.
  • Understanding theophylline pharmacokinetics is crucial for optimizing therapeutic efficacy and minimizing toxicity in children.

Purpose of the Study:

  • To determine theophylline clearance values in South African children.
  • To identify demographic factors influencing theophylline clearance and its interindividual variability.

Main Methods:

  • Population pharmacokinetic analysis using the Non-Linear Mixed Effects Model (Nonmem).
  • Analysis of 400 serum theophylline concentration measurements from 109 pediatric outpatients.
  • Evaluation of fixed effects including age, gender, weight, and race on clearance.

Main Results:

  • Age, gender, and weight were significant demographic factors affecting theophylline clearance.
  • Theophylline clearance decreased with increasing age in children.
  • Weight-adjusted clearance values were 0.0949 L/h/kg (1-5 y), 0.0813 L/h/kg (5-9 y), and 0.0660 L/h/kg (9-16 y).
  • Race was not found to be a significant factor.

Conclusions:

  • Age-adjusted weight-based theophylline clearance values in South African children are comparable to international findings.
  • These findings can inform more precise dosing strategies for theophylline in pediatric populations.

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