Multiple Oral Dose AdministrationObjectives:
==> To recognize and use the integrated equations used to describe plasma
concentrations versus time after multiple oral doses==> To calculate
appropriate multiple dose drug regimen
==> To define, use, and calculate the parameter
So far we have looked at multiple IV bolus administration. In an analogous
fashion, equations can be developed which enable you to calculate the plasma
concentration achieved following multiple oral administration. To start the
plasma concentration achieved following a single oral dose can be given by:-
Equation XV-1 Cp after a Single Oral Dose
This can be converted to an equation describing plasma concentration at any
time following n equal doses with constant dosing interval t.
Equation XV-2, General Equation
Figure XV-1, Plot of Cp Versus Time for Multiple Oral Doses showing Cpmax
and Cpmin
Using a JAVA aware browser you can create your own version of
Figure XV-1.
Plasma Concentration versus Time Plots
The plasma concentration versus time curve described by this equation is
similar to the IV curve in that there is accumulation of the drug in the body to
some plateau level and the plasma concentrations fluctuate between a minimum and
a maximum value.
The Cpmax value can be calculated at the time t = tpeak after many
doses (n ->  )
but it is complicated by the need to determine the value for tpeak.
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