title: Pharmacokinetic profile of dextromethorphan hydrobromide in a syrup formulation in children and adolescents.
abstract: BACKGROUND
  Dextromethorphan hydrobromide (DM) is a widely used antitussive. This study determined, for the first time, the basic pharmacokinetic profile of DM and its active metabolite, dextrorphan (DP) in children and adolescents.
  
  
  METHODS
  Thirty-eight male and female subjects at risk for developing an upper respiratory tract infection (URTI), or symptomatic with cough due to URTI, were enrolled in this single-dose, open-label study: ages 2-5 years (Group A, n = 8), 6-11 years (Group B, n = 17), 12-17 years (Group C, n = 13). Subjects were genotyped for cytochrome P450 (CYP) 2D6 polymorphisms and characterized as poor (PM) or non-poor metabolizers (non-PM). Groups A and B were dosed using an age-weight dosing schedule (DM range 7.5-24.75 mg); a 30-mg dose was used for Group C.
  
  
  RESULTS
  Average exposures to total DP increased as age group increased, and average exposure to DM was highest in the adolescent group. One subject in that group was a PM. The terminal half-life (t ½) values were longer in the adolescent group due in part to the single PM subject. No relationship between body weight and pharmacokinetic parameters was noted.
  
  
  CONCLUSIONS
  This is the first evaluation of the pharmacokinetic characteristics of DM in children and adolescents. A single dose of DM in this population was safe, and well tolerated at all doses tested. The data are used to model and compare pediatric DM exposures with those of adults.
authors.affiliation: Novartis Consumer Health, Inc., Parsippany, NJ, USA, eric.guenin@rb.com.
authors.forename: Eric
authors.initials: E
authors.lastname: Guenin
authors.forename: Marianna
authors.initials: M
authors.lastname: Armogida
authors.forename: Dennis
authors.initials: D
authors.lastname: Riff
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000996:Antitussive Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics*; D002648:Child; D002675:Child, Preschool; D003371:Cough / Q000188:drug therapy* / Q000209:etiology; D019389:Cytochrome P-450 CYP2D6 / Q000235:genetics / Q000378:metabolism*; D003915:Dextromethorphan / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics*; D004305:Dose-Response Relationship, Drug; D005260:Female; D005838:Genotype; D006207:Half-Life; D006801:Humans; D008297:Male; D012141:Respiratory Tract Infections / Q000150:complications / Q000188:drug therapy
chemical_list: D000996:Antitussive Agents; D003915:Dextromethorphan; D019389:Cytochrome P-450 CYP2D6