Premium
Bioavailability of terfenadine in man
Author(s) -
Okerholm R. A.,
Weiner D. L.,
Hook R. H.,
Walker B. J.,
Leeson G. A.,
Biedenbach S. A.,
Cawein M. J.,
Dusebout T. D.,
Wright G. J.,
Myers Mary,
Schindler Valerie,
Cook C. E.
Publication year - 1981
Publication title -
biopharmaceutics and drug disposition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.419
H-Index - 58
eISSN - 1099-081X
pISSN - 0142-2782
DOI - 10.1002/bdd.2510020211
Subject(s) - terfenadine , chemistry , bioavailability , urine , feces , chromatography , crossover study , absorption (acoustics) , excretion , pharmacokinetics , pharmacology , zoology , medicine , biochemistry , paleontology , physics , alternative medicine , pathology , acoustics , biology , placebo
Fourteen normal male subjects were given either 60 mg or 180mg of terfenadine suspension in a randomized two‐way crossover study. Peak plasma concentrations of 1.544 ± 0.726 (mean ± S.D.) ng ml −1 were obtained in 0.786 ± 0.426 h following the 60 mg dose and displayed an AUC of 11.864 ± 3.369 ng h ml −1 . Whereas peak plasma concentrations of 4.519.2 ± 002ng ml −1 in 1.071 ± 0.514h were obtained following the 180mg dose. The AUC following the 180 mg dose was 44.341 ± 22.041 ng h ml −1 . When 60 mg of 14 C terfenadine was given to six additional subjects, the peak plasma concentrations of 351.43ng equivalents per ml were obtained in 1.67 ± 0.41 h and the AUC was 2297.71 ± 310.85ng‐equivalentshml −1 . This indicates that approximately 99.5 per cent of the terfenadine related material that is absorbed undergoes biotransformation. Urinary excretion of 14 C accounted for 39.89 ± 5.29 per cent of the dose while 60.58 ± 2.44 per cent of the dose was recovered in the feces in twelve days. Thin‐layer chromatographic (TLC) examination of fecal extracts showed only a trace of material chromatographing with terfenadine. This may indicate that the 14 C present in the feces is not due to lack of absorption.