Deck 1: Pharmacokinetics and Drug Properties

Question 1

Which of the following is >90% bound to plasma proteins?

A)Atenolol
B)Diazepam
C)Gentamycin
D)Lithium
E)Theophylline

Answer 1

Diazepam

Question 2

Which of the following has the largest volume of distribution?

A)Digoxin
B)Imipramine
C)Lithium
D)Chloroquine
E)Trimethoprim

Answer 2

Chloroquine

Question 3

Which of the following has the shortest half life?

A)Theophylline
B)Diazepam
C)Aspirin
D)Lithium
E)Digoxin

Answer 3

Aspirin

Question 4

Which of the following is a phase one reaction?

A)Reduction
B)Acetylation
C)Glucuronidation
D)Methylation
E)Sulphate conjugation

Question 5

Clearance of which drug involves capacity limited elimination?

A)Theophylline
B)Gentamycin
C)Digoxin
D)Lithium
E)Phenytoin

Question 6

An example of drugs that undergo chemical antagonism is

A)Insulin - glucagon
B)Protamine - heparin
C)Prednisone - glipizide
D)Morphine - naloxone
E)Phenoxybenzamine - prazosin

Question 7

Regarding first order kinetics - all of the following are true EXCEPT

A)First order kinetics means rate of reaction is proportional to concentration
B)First order kinetics is more common than zero order kinetics
C)First order kinetics apply to exponential processes
D)First order kinetics generally apply to high plasma concentrations (>20 mg / 100 ml) of ethanol
E)First order kinetics result in steady state concentrations after multiple dosing.

Question 8

Bioavailability is

A)The difference between the amount of drug absorbed and the amount excreted
B)The proportion of the drug in a formulation that is found in the systemic circulation
C)The AUC relating plasma concentration of drug to time after administration
D)Always identical with different formulations of the same drug
E)A measure of the rate of absorption of a drug

Question 9

Which of the following drugs has a high extraction ratio?

A)Diazepam
B)Theophylline
C)Phenytoin
D)Warfarin
E)Propranolol

Question 10

Regarding biotransformation

A)Phase one reactions always precede phase two reactions
B)Skin is an organ involved in drug biotransformation
C)Water conjugation is a phase one reaction
D)CYP2D6 accounts for the majority of P450 activity
E)Epoxidation is phase two biotransformation

Question 11

Which of the following receptor - ligand pathway is correct?

A)Insulin - G protein receptor
B)Mineralocorticoid - tyrosine kinase receptor
C)Vitamin D - intracellular receptor
D)Adrenaline - ligand gated channel receptor
E)Platelet derived growth factor - cytokine receptor

Question 12

Age associated changes in pharmacokinetics include

A)Reduction in creatinine clearance in 2/3 population
B)Decreased body fat
C)Increase body water
D)A greater reduction in conjugation compared with oxidation
E)A decreased absorption related to age alone

Question 13

The metabolic pathway of detoxification that become increasingly important in paracetamol toxicity is

A)Conjugation with glucuronide
B)Oxidation
C)Reduction
D)Methylation
E)Cytochrome p450 dependent glutathione conjugation

Question 14

You are given a vial with 15 ml of 0.5% prilocaine to do an arm block. How many mg of prilocaine are you injecting?

A)7.5 mg
B)15 mg
C)30 mg
D)50 mg
E)75 mg

Question 15

Drugs that enhance other drug metabolism include all of the following EXCEPT

A)Rifampicin
B)Ketoconazole
C)Phenobarbital
D)Griseofulvin
E)Phenytoin

Question 16

Which is the safest to give in pregnancy?

A)Lithium
B)Phenytoin
C)Gentamycin
D)Heparin
E)ACE inhibitors

Question 17

Regarding pharmacology principles

A)Diffusion is directly proportional to thickness and inversely proportional to surface area
B)LD50 - 50% of the dose that kills most people
C)Efficacy is the maximum response produced by a drug
D)A partial agonist is always less potent than a full agonist
E)EC50 = concentration of agonist that results in maximal response in 50% of patients

Question 18

Reports of cardiac arrhythmias caused by unusually high blood levels of 2 antihistamines (terfenadine and astemizole) are best explained by

A)Concomitant treatment with phenobarbital
B)Use of these drugs by smokers
C)Use of antihistamines by persons of Asian background
D)A genetic predisposition to metabolise succinylcholine slowly
E)Treatment of these patients with ketoconazole

Question 19

Which of the following statements is correct?

A)The half life is the time taken for a parameter to fall to 1/4 its original value
B)Partial agonists act at receptor sites to cause maximal pharmacological effect at high doses
C)Diazepam has a high extraction ratio and is thus subject to flow dependent elimination
D)Morphine and pethidine have the same potency
E)A patient with oedema will have an increased volume of distribution of tobramycin

Question 20

Which of the following drugs has an average half life of 50 hours?

A)Nortriptylline
B)Digoxin
C)Trimethoprim
D)Valproic acid
E)Lithium

Question 21

All of the following have 100% oral bioavailability EXCEPT

A)Valproic acid
B)Trimethoprim
C)Digoxin
D)Diazepam
E)Lithium

Question 22

All of the following drugs are >90% plasma protein bound EXCEPT

A)Diazepam
B)Frusemide
C)Fluoxetine
D)Gentamicin
E)Warfarin

Question 23

Which of the following drugs has a volume of distribution >2000 ?/70kg?

A)Aspirin
B)Imipramine
C)Digoxin
D)Propranolol
E)Chloroquine