Estimation of absorption rate constant (ka) following oral administration by Wagner-Nelson, Loo-Riegelman, and statistical moments in the presence of a secondary peak.
The objective of this study was to evaluate the performance of Wagner-Nelson, Loo-Reigelman, and statistical moments methods in determining the absorption rate constant(s) in the presence of a secondary peak. These methods were also evaluated when there were two absorption rates without a secondary peak. Different sets of plasma concentration versus time data for a hypothetical drug following one or two compartment models were generated by simulation. The true ka was compared with the ka estimated by Wagner-Nelson, Loo-Riegelman and statistical moments methods. The results of this study indicate that Wagner-Nelson, Loo-Riegelman and statistical moments methods may not be used for the estimation of absorption rate constants in the presence of a secondary peak or when absorption takes place with two absorption rates.
Division of Clinical Trial Design and Analysis, Office of Therapeutic Research and Review, Clinical Pharmacology and Toxicology Branch, Food & Drug Administration, Rockville, MD 20852, USA. mahmoodi@cber.fda.gov
Iftekhar
I
Mahmood
D000042:Absorption; D000284:Administration, Oral; D041981:Gastrointestinal Tract / Q000378:metabolism; D006801:Humans; D007275:Injections, Intravenous; D004364:Pharmaceutical Preparations / Q000097:blood; D010599:Pharmacokinetics; D013223:Statistics as Topic
D004364:Pharmaceutical Preparations