Concentration at the end of the first dosing interval
Equation XIV-11 Cp after the First Dose
This gives the plasma concentrations at the end of first interval, where t is the dosing interval in hours.
At the start of the second interval
then at the end of the second dose interval
and so on.
It will help if we define the parameter
which is the fraction of the initial plasma concentration remaining at the end of the dosing interval.
this is a geometric series with each term R times the preceding term.
Equation XIV-12 Cp Immediately after the nth Doses
Equation XIV-13 Cp at the end of nth Dosing Interval
these two sums can be simplified to give
Equation XIV-14 Cp at the Beginning on the nth Dosing Interval
Equation XIV-15 Cp at the End of the nth Dosing Interval
using the first equation (Equation XIV-14) we can calculate the concentration in plasma at any time following uniform multiple IV bolus administration.
where t = time since the last dose. Then
Equation XIV-16 Cp at any Time after n Doses
Copyright 2001 David W.A. Bourne