Page 37 - Interactive Theoritical Notes of Bioharmaceutics and pharamcokinetics.docx compressed

PharmD clinical pharmacy program Level 3, Semester 2 Biopharmaceutics & Pharmacokinetics (PT608(

When drugs are monitored in plasma or serum, it is the concentration (not mass or

amount that is measured. Dividing the equations by volume V, yields
(

Equation Graphs

l

log Cp = log (Cp)o – kt/2.3

Where;

Cpo: Initial drug concentration
Cp: Drug concentration remaining at time
t
K: Reaction rate constant

= . ⁄
½

Where,

: half life time
½
K: Elimination rate constant

Pharmacokinetic parameters

1. Apparent volume of distribution (V d)

(
2. Elimination half-life (t 1/2
3. Elimination rate constant (K or K el)

4. Systemic clearance (Cl s)

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