1.05 - Pharmacokinetics 3 and 4

Question 1

Biotransformation occurs mostly in the ___

Answer 1

Liver

Question 2

Biodegradation can make drugs more ___ (polar or non-polar), thus, more readily excreted

Answer 2

Polar

Question 3

Differentiate active and inactive compounds based on polarity, solubility, and ionization

Answer 3

Active compounds are less polar, less ionized, and lipid soluble

Question 4

Phase of biotransformation where drugs are oxidized or reduced to a more polar, less pharmacologically active form via oxidative, hydrolytic, and reductive reactions

Answer 4

Phase I or non-synthetic phase

Question 5

Phase of biotransformation where drugs are conjugated with acetate, glucoronate, sulfate, or glycine

Answer 5

Phase II or synthetic phase

Question 6

___ is the most common conjugation reaction

Answer 6

Glucoronidation (e.g. glucoronosyl transferase)

Question 7

In general, asians are __ (slow or rapid) acetylators

Answer 7

Rapid

Question 8

Metabolism of Theophylline is induced by ___

Answer 8

Benzo (a) pyrene

Question 9

Metabolism of Barbiturates, chloramphenicol, anticoagulants, digitoxin, doxorubicin is induced by ___

Answer 9

Phenobarbital and other barbiturates

Question 10

Metabolism of cortisol, dexamethasone, digitoxin, theophylline is induced by ___

Answer 10

Phenytoin

Question 11

Metabolism of Coumarin anticoagulants, digitoxin, glucocorticoids, propranolol is induced by ___

Answer 11

Rifampicin

Question 12

Metabolism of warfarin is induced by ___

Answer 12

Griseofulvin

Question 13

___ decreases metabolism of probenecid

Answer 13

Allopurinol, chloramphenicol, isoniazid

Question 14

___ decreases metabolism of phenytoin

Answer 14

Dicumarol

Question 15

___ decreases metabolism of warfarin

Answer 15

Cimetidine

Question 16

___ decreases metabolism of theophylline

Answer 16

Erythromycin

Question 17

___ decreases metabolism of terfenadine

Answer 17

Ketoconazole

Question 18

____ (polar or nonpolar) substances has shorter retention time, easily excreted, and difficult to be absorbed

Answer 18

Polar

Question 19

The ___ (zero or first) order kinetics is where a constant fraction or percentage of the drug is handled per unit time; dependent on drug concentration; linear, non-saturable

Answer 19

First order kinetics

Question 20

The __ (zero or first) order kinetics is non-linear, saturable, where a constant amount of drug is handled per unit time; dependent on rate constant of the process

Answer 20

Zero order kinetics

Question 21

Enumerate the 5 well-studied drugs that follow zero order kinetics

Answer 21

Mnemonic: Pro-PADE
Probenecid
Phenytoin
Aspirin
Dicoumarol
Ethanol

Question 22

Enumerate the three most important pharmacokinetic parameters

Answer 22

Bioavailability
Volume of distribution
Clearance

Question 23

___ is the fraction of the drug that remains unchanged once it reaches the circulation

Answer 23

Bioavailability

Question 24

What does a low volume of distribution (Vd) mean?

Answer 24

The drug remains within the vascular component (may be due to high degree of protein binding, very low lipid water partition coefficient, low permeability to membranes)

Question 25

What does a high volume of distribution mean?

Answer 25

The drug has been widely absorbed by the tissues (may be due to increased solubility of the drug)

Question 26

___ is a measure of how efficient the system is in removing the drug

Answer 26

Clearance

Question 27

The half-life concept is only applicable to drugs with (first or zero) ___ order kinetics

Answer 27

First order kinetics

Question 28

Aspirin has a half-life of __ hours

Answer 28

4 hours

Question 29

Digitoxin has a half-life of ___ days

Answer 29

7 days

Question 30

If the graph of therapeutic range is steep, the therapeutic window is ____

Answer 30

Narrow therapeutic window

Question 31

If the graph of therapeutic range is more slanted/diagonal, the therapeutic window is ____

Answer 31

Wide therapeutic window (therefore, relatively safe)

Question 32

Ibuprofen has a ___ (narrow or wide) therapeutic window

Answer 32

Wide therapeutic window

Question 33

Theophylline has a ___ (narrow or wide) therapeutic window

Answer 33

Narrow therapeutic window