ISSN:
1573-904X
Keywords:
ibuprofen enantiomers
;
pharmacokinetics
;
bioinversion
;
bioavailability
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract An open, randomized, six-way crossover study was conducted in 12 healthy males to assess pharmacokinetics and bioinversion of ibuprofen enantiomers. The mean plasma terminal half-life (t1/2) of R(–)ibuprofen was 1.74 hr when intravenously infused as a racemic mixture and was 1.84 hr when intravenously infused alone. The mean t1/2 of S( + )ibuprofen was 1.77 hr when dosed as S( + )ibuprofen. Examination of values of both the absorption and disposition parameters of R(–)ibuprofen revealed that the kinetics of R(–)ibuprofen were not altered by concurrent administration of S( + )ibuprofen. In this study, there was little or no presystemic inversion of R(–)ibuprofen to its S( + )isomer. Also, 69% of the intravenous dose of R(–)ibuprofen was systemically inverted and 57.6% of the oral dose of R(–)ibuprofen lysinate was bioavailable as S ( + )ibuprofen. These results indicate that the bioinversion of R(–)ibuprofen administered orally is mainly systemic. Because bioinversion of R(–)ibuprofen is not complete, S( + )ibuprofen produced higher bioavailability of S( + )ibuprofen (92.0%) than either racemic ibuprofen (70.7%) or R(–)ibuprofen (57.6%). However, bioavailability of R(–)ibuprofen (83.6%) when dosed alone was not significantly different from when dosed as racemic mixture (80.7%).
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1018969506143
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