title: Pharmacogenetics and development: are infants and children at increased risk for adverse outcomes?
abstract: Over the past two decades, pharmacokinetic data have clearly demonstrated that development can markedly influence the absorption, distribution, excretion, and metabolism of xenobiotics. With respect to many of the processes that govern drug metabolism, the underlying pharmacogenetic determinants that may control either the affinity or the capacity of a drug or toxicant substrate for the enzymes responsible for its biotransformation appear to be altered as a function of development by mechanisms that are, for the most part, not well defined. Nonetheless, for many xenobiotics, the pharmacogenetic-developmental interface produces a "pattern" for drug metabolism that, when characterized, supports the pharmacokinetic properties (eg, drug clearance) reported for many agents across the pediatric age spectrum. With the exception of a few relatively well-characterized adverse drug effects (eg, toxicity of 6-mercaptopurine in patients with absent thiopurine methyltransferase activity, increased incidence of hepatotoxicity to valproic acid in young infants), the relationship of development and pharmacogenetics to enhanced toxicity risk from xenobiotic exposure is poorly defined. However, failure to adequately appreciate the pharmacokinetic consequences of the pharmacogenetic-developmental interface and to individualize therapy accordingly may lead to a clinically significant risk of drug therapy, namely, over- or underdosing.
authors.affiliation: University of Arkansas for Medical Sciences, Little Rock, USA.
authors.forename: G L
authors.initials: GL
authors.lastname: Kearns
mesh_terms: D000426:Alcohol Dehydrogenase / Q000493:pharmacokinetics; D001191:Arylamine N-Acetyltransferase / Q000493:pharmacokinetics; D001711:Biotransformation; D002648:Child; D002675:Child, Preschool; D019388:Cytochrome P-450 CYP1A2; D019389:Cytochrome P-450 CYP2D6; D019392:Cytochrome P-450 CYP2E1; D003577:Cytochrome P-450 Enzyme System / Q000493:pharmacokinetics; D004851:Epoxide Hydrolases / Q000493:pharmacokinetics; D006801:Humans; D007223:Infant; D006899:Mixed Function Oxygenases / Q000493:pharmacokinetics; D010088:Oxidoreductases / Q000493:pharmacokinetics; D010597:Pharmacogenetics; D010601:Pharmacology, Clinical
chemical_list: D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases; D010088:Oxidoreductases; D000426:Alcohol Dehydrogenase; D019392:Cytochrome P-450 CYP2E1; D019388:Cytochrome P-450 CYP1A2; D019389:Cytochrome P-450 CYP2D6; D001191:Arylamine N-Acetyltransferase; D004851:Epoxide Hydrolases