## Repetitive Intravenous Dosing

## In repetitive dosing, the plasma concentration at the end of the first dosing interval is given by:

(1)

C_{P1}^{T}=C_{P1}^{O}exp(-k_{el}T)Immediately after the second dose is injected, the plasma [ ] will be,

(2)

C_{P2}^{O}=C_{P1}^{T }+C_{P1}^{O }=C_{P1}^{O}exp(-k_{el}T) +C_{P1}^{O}and so on.We then need to define a certain parameter R, which is the fraction of the initial plasma concentration that remains at the end of any dosing interval. R is given as

(3) R = exp(-

k_{el}T) = 10^{-(kelT /2.30)}Equations (1) and (2) are simplified into

C_{P1}^{T }=C_{P1}^{O}Rfor the plasma concentration at the end of the first dosing interval, and

C_{P2}^{O}=C_{P1}^{O}R +C_{P1}^{O}for the plasma concentration at the beginning and end of the

nth dosing interval.

B.9b-1