Back to the Top
Hello everyone,
I have been asked to calculate the AUC(alpha) and AUC(beta) for a drug. I
have never explicitly heard of these terms. Has anyone have experience with
them? How do you calculate them noncompartmentally and/or compartmentally?
I have an idea of their purpose and how to calculate them, but your expert
opinions would be greatly appreciated.
Thanks.
Matt
[A/alpha for one and B/beta for the other? - db]
Back to the Top
It is not possible, as far as I know, to calculate them
noncompartmentally because you need to know the coefficients and
exponents of the biexponential model.
AUCalpha = A/alpha or C1/lambda1
AUCbeta = B/beta or C2/lambda2
Their use is to calculate the relative contributions of the two
phases of the profile to the clearance of the drug. If the terminal
phase is the dominant phase then AUCbeta will contribute the majority
of the total AUC. If AUCalpha is dominant then you have a drug which
is eliminated faster than its distribution and the terminal half-life
reflects distribution rather than elimination. In this case
calculation of an effective half-life from MRT x 0.693 is appropriate.
regards
Brian
PharmPK Discussion List Archive Index page
Copyright 1995-2010 David W. A. Bourne (david@boomer.org)