title: Effects of urine alkalization and activated charcoal on the pharmacokinetics of orally administered carprofen in dogs.
abstract: OBJECTIVE
  To investigate the effects of oral administration of activated charcoal (AC) and urine alkalinization via oral administration of sodium bicarbonate on the pharmacokinetics of orally administered carprofen in dogs.
  
  
  METHODS
  6 neutered male Beagles.
  
  
  METHODS
  Each dog underwent 3 experiments (6-week interval between experiments). The dogs received a single dose of carprofen (16 mg/kg) orally at the beginning of each experiment; after 30 minutes, sodium bicarbonate (40 mg/kg, PO), AC solution (2.5 g/kg, PO), or no other treatments were administered. Plasma concentrations of unchanged carprofen were determined via high-performance liquid chromatography at intervals until 48 hours after carprofen administration. Data were analyzed by use of a Student paired t test or Wilcoxon matched-pairs rank test.
  
  
  RESULTS
  Compared with the control treatment, administration of AC decreased plasma carprofen concentrations (mean +/- SD maximum concentration was 85.9 +/- 11.9 mg/L and 58.1 +/- 17.6 mg/L, and area under the time-concentration curve was 960 +/- 233 mg/L x h and 373 +/- 133 mg/L x h after control and AC treatment, respectively). The elimination half-life remained constant. Administration of sodium bicarbonate had no effect on plasma drug concentrations.
  
  
  CONCLUSIONS
  After oral administration of carprofen in dogs, administration of AC effectively decreased maximum plasma carprofen concentration, compared with the control treatment, probably by decreasing carprofen absorption. Results suggest that AC can be used to reduce systemic carprofen absorption in dogs receiving an overdose of carprofen. Oral administration of 1 dose of sodium bicarbonate had no apparent impact on carprofen kinetics in dogs.
authors.affiliation: Department of Equine and Small Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, FIN-00014, Finland.
authors.forename: Marja R
authors.initials: MR
authors.lastname: Raekallio
authors.forename: Juhana M
authors.initials: JM
authors.lastname: Honkavaara
authors.forename: Mia S
authors.initials: MS
authors.lastname: Säkkinen
authors.forename: S Marikki
authors.initials: SM
authors.lastname: Peltoniemi
mesh_terms: D000818:Animals; D002227:Carbazoles / Q000097:blood / Q000378:metabolism* / Q000493:pharmacokinetics*; D002606:Charcoal / Q000378:metabolism / Q000494:pharmacology*; D002851:Chromatography, High Pressure Liquid; D004285:Dogs; D008297:Male; D017693:Sodium Bicarbonate / Q000494:pharmacology* / Q000652:urine; D013997:Time Factors
chemical_list: D002227:Carbazoles; D002606:Charcoal; D017693:Sodium Bicarbonate; C007005:carprofen