title: Pharmacokinetic-pharmacodynamic study of oral lansoprazole in children.
abstract: OBJECTIVE
  We investigated the pharmacokinetics, pharmacodynamics, and tolerability of lansoprazole in children after single and multiple administrations.
  
  
  METHODS
  Forty children (age range, 18 days-14 years) with gastric acid-related disorders entered an open study and received lansoprazole in a single dose of 17 mg. m(-2) (group A) or in multiple doses (17 mg. m(-2) per day) for 7 to 14 days (group B). Lansoprazole plasma concentrations were measured by HPLC. A 24-hour intragastric pH monitoring assessed the antisecretory effect.
  
  
  RESULTS
  In group A, maximal concentration (C(max)) was 1023 +/- 775 (mg. L(-1))/(17 mg. m(-2)), time to reach C(max) was 1.8 +/- 0.8 hours, elimination half-life was 1.5 +/- 2.0 hours, area under the concentration-time curve from time zero to infinity [AUC(0-infinity)] was 3503 +/- 6025 (mg. L(-1). h)/(17 mg. m(-2)), apparent plasma clearance was 0.57 +/- 0.47 L. h(-1). kg(-1), and apparent volume of distribution was 0.61 +/- 0.36 L. kg(-1). In group B, C(max) was 750 +/- 511 (mg. L(-1))/(17 mg. m(-2)), time to reach C(max) was 1.8 +/- 1.1 hours, elimination half-life was 1.2 +/- 1.1 hours, AUC(0-infinity) was 2351 +/- 3691 (mg. L(-1). h)/(17 mg. m(-2)), apparent plasma clearance was 0.71 +/- 0.50 L. h(-1). kg(-1), and apparent volume of distribution was 0.9 +/- 0.7 L. kg(-1). No influence of age was shown on pharmacokinetic parameters in both groups. However, data suggested that elimination was reduced in neonates and higher in infants than in adults. The values for 24-hour percentage of time at gastric pH <4 and pH <3 were 61% +/- 21% and 51% +/- 21% (group A) and 47% +/- 24% and 37% +/- 21% (group B), respectively. In both groups the antisecretory effect decreased with age, and in group A it was positively correlated to C(max) and AUC(0-infinity). The mean gastrin serum concentration significantly increased (+31%) after 12.6 +/- 1.5 days of treatment.
  
  
  CONCLUSIONS
  Lansoprazole was well tolerated in children. After a single oral dose of 30 mg per 1.73 m(2), there was a trend for the elimination to be higher in infants than in adults and the antisecretory effect appeared to be higher in infants younger than 6 months than in older children and adults.
authors.affiliation: Pharmacologie Périnatale et Pédiatrique, Gastroentérologie Pédiatrique, Université René Descartes, Hôpital Saint-Vincent de Paul, 82 Avenue Denfert-Rochereau, Assistance Publique-Hôpitaux de Paris, 75674 Paris, France.
authors.forename: Agnès
authors.initials: A
authors.lastname: Tran
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Rey
authors.forename: Gérard
authors.initials: G
authors.lastname: Pons
authors.forename: Ann
authors.initials: A
authors.lastname: Pariente-Khayat
authors.forename: Philippe
authors.initials: P
authors.lastname: D'Athis
authors.forename: Valentine
authors.initials: V
authors.lastname: Sallerin
authors.forename: Christophe
authors.initials: C
authors.lastname: Dupont
mesh_terms: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000284:Administration, Oral; D000293:Adolescent; D000897:Anti-Ulcer Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics / Q000494:pharmacology; D019540:Area Under Curve; D002648:Child; D002675:Child, Preschool; D004334:Drug Administration Schedule; D004341:Drug Evaluation / Q000379:methods / Q000706:statistics & numerical data; D005745:Gastric Acidity Determination; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D064747:Lansoprazole; D009853:Omeprazole / Q000008:administration & dosage* / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000493:pharmacokinetics* / Q000494:pharmacology; D054328:Proton Pump Inhibitors; D018709:Statistics, Nonparametric
chemical_list: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000897:Anti-Ulcer Agents; D054328:Proton Pump Inhibitors; D064747:Lansoprazole; D009853:Omeprazole