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Drug metabolizing enzymes in the perinatal and neonatal period: differences in the expression and activity

Laura Cuzzolin1

  • 1Department of Public Health & Community Medicine-Section of Pharmacology, University of Verona, Policlinico G.B. Rossi, Piazzale L.A. Scuro, 37134 Verona, Italy. laura.cuzzolin@univr.it

Current Drug Metabolism
|September 1, 2012
PubMed

Insights

Neonatal drug metabolism is immature, impacting treatment efficacy and toxicity. This review covers differences in drug-metabolizing enzymes and their clinical relevance in newborns.

Area of Science:

  • Pharmacology
  • Neonatal Medicine
  • Drug Metabolism

Background:

  • Physiological changes during the perinatal period and early infancy significantly influence drug response.
  • Drug efficacy and toxicity exhibit high variability in the neonatal population.
  • Immature drug metabolism is a key factor contributing to this variability.

Purpose of the Study:

  • To review qualitative and quantitative differences in neonatal drug-metabolizing enzymes.
  • To examine the immaturity of Phase I and Phase II metabolic pathways at birth.
  • To discuss the maturational changes in these pathways during early extrauterine life.

Main Methods:

  • Literature review of studies on drug metabolism in neonates.
  • Analysis of data on Phase I and Phase II enzyme activity and expression.
  • Synthesis of information on developmental changes in metabolic pathways.

Main Results:

  • Both Phase I and Phase II drug metabolism pathways are immature in neonates.
  • Significant maturational changes occur in these pathways in the first month of life.
  • Enzyme activity and expression levels differ qualitatively and quantitatively compared to adults.

Conclusions:

  • Neonatal immaturity of drug metabolism significantly affects pharmacological treatment outcomes.
  • Understanding these metabolic differences is crucial for optimizing drug therapy in newborns.
  • Clinical implications of altered drug metabolism in neonates warrant careful consideration.

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