title: Pharmacokinetics of an extended-release theophylline product in cats.
abstract: OBJECTIVE
  To evaluate the pharmacokinetics of a brand of extended-release theophylline tablets and capsules in healthy cats.
  
  
  METHODS
  Randomized 3-way crossover study.
  
  
  METHODS
  6 healthy cats.
  
  
  METHODS
  A single dose of aminophylline (10 mg/kg [4.5 mg/lb], IV), a 100-mg extended-release theophylline tablet, or a 125-mg extended-release theophylline capsule was administered to all cats. Plasma samples were collected via preplaced central catheters throughout a 36-hour period. Plasma samples were frozen until analyzed by use of a fluorescence polarization monoclonal immunoassay.
  
  
  RESULTS
  All cats tolerated drug administration and plasma collection with no adverse effects. Peak concentrations were reached for both orally administered products between 8 and 12 hours after administration. Bioavailability was excellent. Plasma concentrations were within the human therapeutic concentration of 5 to 20 microg/mL.
  
  
  CONCLUSIONS
  Daily administration of the brand of theophylline tablets and capsules used in this study at 15 mg/kg (6.8 mg/lb) and 19 mg/kg (8.6 mg/lb), respectively, maintained plasma concentrations within the desired therapeutic range in healthy cats.
authors.affiliation: Wheat Ridge Veterinary Specialists, Wheat Ridge Animal Hospital, 3695 Kipling St, Wheat Ridge, CO 80033, USA.
authors.forename: Christine L
authors.initials: CL
authors.lastname: Guenther-Yenke
authors.forename: Brendan C
authors.initials: BC
authors.lastname: McKiernan
authors.forename: Mark G
authors.initials: MG
authors.lastname: Papich
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Powell
mesh_terms: D000284:Administration, Oral; D000818:Animals; D019540:Area Under Curve; D001682:Biological Availability; D001993:Bronchodilator Agents / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D002214:Capsules; D002415:Cats / Q000097:blood / Q000378:metabolism* / Q000652:urine; D018592:Cross-Over Studies; D003692:Delayed-Action Preparations; D007275:Injections, Intravenous / Q000662:veterinary; D013607:Tablets; D013806:Theophylline / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine
chemical_list: D001993:Bronchodilator Agents; D002214:Capsules; D003692:Delayed-Action Preparations; D013607:Tablets; D013806:Theophylline