title: Lack of effect of gender and oral contraceptive steroids on the pharmacokinetics of (R)-ibuprofen in humans.
abstract: The effects of gender and oral contraceptive steroids on the pharmacokinetics of (R)-ibuprofen were studied in groups of healthy adult males, females and oral contraceptive steroid (OCS) using females. The values of AUC, CLpo, t1/2 and Vss, app did not differ significantly between the groups. Similarly, the percentage unbound of (R)-ibuprofen in pooled plasma from the three groups was not statistically different. Since chiral inversion is the major determinant of (R)-ibuprofen clearance in humans, it may be inferred from these data that gender and OCS have little or no effect on conversion of (R)-ibuprofen to the pharmacologically active S-enantiomer. Moreover, it is unlikely that hormonal factors influence the activity of the human hepatic long-chain fatty-acid:CoA ligase, the enzyme mediating the rate limiting step of (R)-ibuprofen inversion.
authors.affiliation: Department of Clinical Pharmacology, Flinders University of South Australia, Bedford Park.
authors.forename: K M
authors.initials: KM
authors.lastname: Knights
authors.forename: C F
authors.initials: CF
authors.lastname: McLean
authors.forename: A L
authors.initials: AL
authors.lastname: Tonkin
authors.forename: J O
authors.initials: JO
authors.lastname: Miners
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D003278:Contraceptives, Oral, Hormonal / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007052:Ibuprofen / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D008297:Male; D012737:Sex Factors; D013237:Stereoisomerism
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D003278:Contraceptives, Oral, Hormonal; D007052:Ibuprofen