Premium
Pseudoephedrine absorption from controlled release formulations: Absorption rate constant estimation methods
Author(s) -
Graves David A.,
Rotenberg Keith S.
Publication year - 1989
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.2510100203
Subject(s) - absorption (acoustics) , mathematics , bioavailability , nonlinear regression , linear regression , elimination rate constant , chemistry , statistics , plasma concentration , analytical chemistry (journal) , regression analysis , chromatography , pharmacokinetics , physics , pharmacology , biology , acoustics , volume of distribution
Five methods of absorption rate ( K a ) estimation were compared using data from a previously reported bioavailability study: Wagner‐Nelson (WN), asymptotic WN (AWN), the Hendeles‐Weinberger modification of the WN (HW), nonlinear regression performed on plasma concentration vs time data with fixed elimination rates (NL), and nonlinear regression performed on the cumulative sum of AUCs obtained during WN analysis (AUCNL). The maximum plasma concentration ( C max ) and the time at which C max occurred ( T max ) were predicted with each method's respective K a 's, and these were compared to observed values. The WN and HW were consistently biased in their predictions of C max and T max , providing slower K a 's than any of the other methods. AWN could only be used for the reference treatment. Both NL and AUCNL provided unbiased estimations, but AUCNL had a high level of imprecision. With this set of data, only NL was an acceptable method for accurately estimating K a .