(3) Pharmacokinetics

Question 1

4 domains of pharmacokinetics

Answer 1

Absorption, Distribution, Metabolism (biotransformation), Elimination

Question 2

Which route of administration does NOT bypass the hepatic portal vein?

Answer 2

Oral

Question 3

First pass effect

Answer 3

Drugs from GI tract metabolized by liver before reaching circulation

Question 4

Bioavailability (F)

Answer 4

Fraction of drugs actually entering circulation

Question 5

What is the bioavailability for parenteral drugs (IV, IM, SC)?

Answer 5

100%

Question 6

Volume of distribution definition

Answer 6

Measure of extent of distribution

Question 7

Volume of distribution (Vd) calculation

Answer 7

Dose present in body/ plasma concentration

Question 8

Metabolism Phase I reaction

Answer 8

Addition of small polar groups via oxidation, reduction, or hydrolysis via Cytochrome P450

Question 9

Metabolism Phase II reaction

Answer 9

Formation of highly water soluble conjugates

Question 10

Zero-Order Elimination

Answer 10

Rate of elimination is constant. Clearance inversely proportional to drug concentration

Question 11

Name 3 drugs eliminated via Zero-Order Elimination

Answer 11

PDE- phenytoin, aspirin, ethanol

Question 12

First Order Elimination

Answer 12

Rate of elimination proportional to plasma drug concentration

Question 13

Elimination Rate Constant (Ke)

Answer 13

Fraction of drug eliminated over a set period of time

-slope of first-order elimination plotted on semi-log graph

Question 14

Calculation for half-life

Answer 14

=0.7/Ke or (0.7xVd)/Cl

Question 15

Loading dose

Answer 15

Dose to achieve steady state

Dose= Vdx C (desired concentration)