Pharmacological Approach to Combat Mosquito Transmitted Malaria

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Figure 10.3: A graph Illustrating the phases of a plasma concentration-time curve of a

two-compartment model of an orally administered drug.

nation of drug from central compartment in relation to the distribution and elimination rate

constants and the inter-compartmental constant K21 as follows:

K10 = ^αβ

K21

(10.1)

The rate constant for the movement of the antimalarial drug from peripheral compartment

to the central compartment (K21):

K21 = Aα+

Bβ

(A+B)

(10.2)

and the rate constant from movement from central compartment to peripheral compartment

(K12) :

K12 = α+β −K21 −K10

(10.3)

The estimation of volumes of distribution, in two-compartment model are as follows:

• The volume of distribution in the central compartment (Vc) of an intravenously ad-

ministered antimalarial is given by,

Vc = ^X0

C0

(10.4)

• For the extravascular route the X0 is replaced by FX0, where F is the bioavailability

of the drug. Therefore, the apparent volume of distribution (Vb) of drug in the body

is used (Vb) and given by (for intravenous route):

Vb =

X0

β (AUC0−∞)

(10.5)