Page 31 - Pharmacology Mnemonics and Short Notes

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Formula

Rate of elimination of Drug
Cl =
Plasma concentration of drug
Rate of Clearance

First order kinetics  constant
Dependence of Clearance
 Blood flow

 Condition of organ eliminating
Clearance of Drug by an organ = extraction capability of that drug x
rate of delivery of that drug to that organ

Bioavailability

Is the percent of unchanged drug reaching systemic circulation after
administration by any route.
In case of I.V. administration, bioavailability will be 100%.

By other routes
Absorption is less than 100
 Due to incomplete absorption

 Due to first pass metabolism
 Distribution into tissue before drug enters the circulation

 Drug formulation
Bioavailability  measured by area under plasma concentration curve

Plasma half-life (t1/2)

Contents

Pharmacology Mnemonics and Short Notes By Muhammad Ramzan Ul Rehman