title: Clinical pharmacokinetic of celecoxib in healthy Thai volunteers.
abstract: BACKGROUND
  Celecoxib, a nonsteroidal antiinflammatory drug exhibits its antiinflammatory effect by selective inhibition of cyclooxygenase-2 (COX-2) enzyme. Its efficacy has been accepted for the treatment of arthritic pain with superior gastrointestinal side effect profile compared with other conventional NSAIDs.
  
  
  OBJECTIVE
  To elucidate clinical pharmacokinetic of celecoxib following an oral dose administration.
  
  
  METHODS
  Eighteen healthy Thai male volunteers were enrolled in the present study. Their mean age was 20.94 +/- 1.21 years and their mean weight was 63 +/- 5.17 kg. They were orally administered 200 mg celecoxib after an over night fasting, serial blood samples were drawn before and at 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 8, 10, 12, 24 and 48 hours after dosing. Plasma celecoxib was analysed by reversed-phase HPLC.
  
  
  RESULTS
  Following a 200 mg celecoxib oral administration, the drug was absorbed into the systemic circulation and reach maximum concentration (Tmax) within 2.50 +/- 1.22 hrs by average with the mean peak concentration (Cmax) of 686.83 +/- 211.35 ng/ml. The extent of absorption (area under the curve, AUC) was approximately 5157.12 +/- 1499.46 and 5911.48 +/- 1363.51 ng hr/ml for AUC(0-->t) and AUC(0-->infinity) respectively. The apparent volume of distribution (Vd) was found to be 458.93 +/- 323.28 L/hr. Celecoxib was eliminated after biotransformation and the metabolites were excreted in both urine and feces. The elimination half-life (t(1/2)) of celecoxib appeared to be 8.79 +/- 5.49 hrs with the apparent clearance (CL) of 35.91 +/- 9.85 L. The elimination rate constant for celecoxib obtained from this present study was about 0.11 +/- 0.05 hr(-1).
  
  
  CONCLUSIONS
  Pharmacokinetic parameters following an oral dose of 200 mg celecoxib administration were characterized, including Cmax, Tmax, Vd, kel, CL, AUC. These parameters reflected absorption, distribution, biotransformation and excretion of celecoxib in healthy Thai volunteers.
authors.affiliation: Department of Pharmacology, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Chandhanee
authors.initials: C
authors.lastname: Itthipanichpong
authors.forename: Sumana
authors.initials: S
authors.lastname: Chompootaweep
authors.forename: Supeecha
authors.initials: S
authors.lastname: Wittayalertpanya
authors.forename: Wandee
authors.initials: W
authors.lastname: Kemsri
authors.forename: Nongnuch
authors.initials: N
authors.lastname: Thaworn
authors.forename: Pajaree
authors.initials: P
authors.lastname: Lilitkarntrakul
authors.forename: Sithiporn
authors.initials: S
authors.lastname: Parikamsil
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D000068579:Celecoxib; D016861:Cyclooxygenase Inhibitors / Q000008:administration & dosage / Q000493:pharmacokinetics*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008297:Male; D011720:Pyrazoles / Q000008:administration & dosage / Q000493:pharmacokinetics*; D012016:Reference Values; D013449:Sulfonamides / Q000008:administration & dosage / Q000493:pharmacokinetics*; D013785:Thailand
chemical_list: D016861:Cyclooxygenase Inhibitors; D011720:Pyrazoles; D013449:Sulfonamides; D000068579:Celecoxib