Deck 2: An Introduction to Pharmacodynamics and Pharmacokinetics

Question 1

The thiazide diuretic hydrochlorothiazide is an example of a drug that acts on which type of receptor?

A)Ion channel
B)Nuclear receptors
C)G-protein receptor complex
D)Second messenger systems

Answer 1

Ion channel

Question 2

Drugs can act on enzymes to cause a variety of effects.Aspirin and NSAIDs exert their anti-inflammatory effects by which of the following mechanisms?

A)Cyclooxygenase (COX)enzyme inhibition
B)Xanthine oxidase inhibition
C)cAMP inhibition
D)Lipooxygenase inhibition

Answer 2

Cyclooxygenase (COX)enzyme inhibition

Question 3

Which factor does not help to determine the way a receptor will respond to a drug?

A)Receptor's affinity for the drug
B)Efficacy of the drug
C)Potency of the drug
D)Therapeutic index of a drug

Answer 3

Therapeutic index of a drug

Question 4

Which option is not one of the five parameters of pharmacokinetics?

A)Absorption
B)Distribution
C)Tachyphylaxis
D)Metabolism

Question 5

Which option best defines the term affinity?

A)The ability of a drug to initiate a biological effect upon binding to receptors
B)The quantity of a drug relative to the number of its receptors
C)The minimum effective dose of a drug
D)The strength of binding between a drug and its receptor

Question 6

Which receptor type is most common in humans and acts as a receptor for many hormones,acetylcholine,adrenoreceptors,and chemokines?

A)Transmembrane G-protein coupled receptor
B)Second messenger systems
C)Ion channels
D)Nuclear receptors

Question 7

Which statement regarding drug-receptor behavior is correct?

A)The intensity of response is proportional to the number of receptors occupied.
B)A drug's intensity and duration of effect are irreversible because forces holding the drug to its receptor are strong.
C)All receptors for drugs are located externally on the cell membrane.
D)All drugs are selective in that they bind to one type of receptor and produce very predictable and specific effects.

Question 8

Drug A binds to its receptor and remains bound despite increasing concentrations of an agonist.Drug A is which type of drug?

A)Competitive antagonist
B)Noncompetitive antagonist
C)Partial agonist
D)Full agonist

Question 9

Which statement best defines the term ED50?

A)The dose at which 50% of a population of human test subjects will respond with an expected effect.
B)The dose at which 50% of a population of human test subjects would die from taking a drug.
C)The dose at which 50% of a population of animals would produce signs of toxicity.
D)The ratio between the lethal and the effective dose.

Question 10

The pharmacologic term selectivity refers to:

A)Drugs that have a preference for acting at certain binding sites or receptors.
B)Drugs that bind to receptors via covalent bonds.
C)Drugs that have a strong dose-response curve.
D)Drugs that act as enzyme inhibitors.

Question 11

Drug A activates beta-receptors but has less of an effect than epinephrine,one of the endogenous agonists for beta-receptors.Which term best describes drug A?

A)Partial agonist
B)Competitive antagonist
C)Irreversible antagonist
D)Full agonist

Question 12

The margin of safety between the dose needed to produce benefits and the dose needed to cause harmful or toxic effects is known as the:

A)Therapeutic index.
B)Effective dose (ED50).
C)Dose response effect.
D)Area under the curve.

Question 13

Which statement regarding an antagonist is true?

A)Antagonists produce their effect by changing the receptor.
B)Antagonists bind and block the effect of an endogenous agonist.
C)Antagonists have an affinity for activating cell receptors.
D)Antagonists induce the same response produced by the endogenous substance.

Question 14

A prescriber is considering ordering a drug that has a high clearance rate,meaning that it is rapidly eliminated from the blood through the kidneys.Which statement is true regarding how the medication should be dosed?

A)Lower doses are needed to keep the active compounds working.
B)Higher doses are needed to keep the active compounds working.
C)No dosing changes need to be made for this medication.
D)Clearance rate has nothing to do with dosing medications.

Question 15

The drug name "fluoxetine" is a:

A)Chemical name.
B)Generic name.
C)Trade name.
D)Brand name.

Question 16

Common bonds that drugs use to fit to their receptor sites include all of the following except:

A)Ionic bonding.
B)Van der Waals bonding.
C)Hydrogen bonding.
D)Compound bonding.

Question 17

Which statement regarding drug receptor activity is not true?

A)A drug can produce numerous effects if more than one set of receptors responds to it.
B)Intensity of response is proportional to the number of receptors occupied.
C)Receptors exist exclusively on a cell membrane.
D)All receptors of a given type are identical and equally accessible to drugs.

Question 18

The drug name "Tylenol" is a:

A)Chemical name.
B)Generic name.
C)Trade name.
D)Clinical name.

Question 19

If drug A and drug B are both agonists and drug A produces a maximum pharmacological response at half the dose of drug B,then drug A is:

A)Half as potent as drug B
B)Twice as potent as drug B
C)As potent as drug B
D)Three times as potent as drug B

Question 20

Which of the following drugs is an antagonist?

A)salmeterol (Serevent)
B)norepinephrine
C)propanolol
D)albuterol (Proventil)

Question 21

Drug distribution is not dependent on which of the following drug properties?

A)Ability of a drug to permeate capillaries
B)First-pass effect
C)A drugs ability to bind to plasma proteins
D)Fat- or water-soluble characteristics

Question 22

In the highly acidic pH of the stomach,which drugs would be best absorbed?

A)Acidic drugs
B)Neutral drugs
C)Basic drugs
D)pH has no affect on absorption

Question 23

P-glycoprotein is a carrier or transporter that brings drugs across cell membranes.Which statement is true regarding P-glycoprotein?

A)P-glycoprotein is responsible for the transport of hydrophilic substances.
B)Grapefruit juice can interact with P-glycoprotein and change the bioavailability of certain drugs.
C)P-glycoprotein is found exclusively on small intestine villi.
D)Changes in P-glycoproteins are unlikely to affect the distribution and elimination of drugs.

Question 24

Which statement is true regarding factors that affect the absorption of drugs?

A)pH has no affect on drug absorption.
B)Increased blood flow to the gastrointestinal tract decreases absorption of orally administered drugs.
C)The solubility of drugs affects their absorption.
D)Absorption is not proportional to the surface area available.

Question 25

Which statement is true regarding renal excretion of drugs?

A)Tubular secretion is the way in which most drugs are removed by the kidneys.
B)Renal blood flow does not affect excretion of drugs.
C)Large-molecular-weight drugs,such as heparin,are easily filtered by the glomeruli.
D)Drugs that are tightly bound to plasma protein are readily filtered by the glomeruli.

Question 26

The predominant organ of drug excretion is the:

A)Liver.
B)Small intestine.
C)Skin.
D)Kidney.

Question 27

The liver enzymes responsible for the metabolism of approximately 75% of drugs are:

A)Cytochrome P450 enzymes.
B)Acetylation enzymes.
C)Esterases.
D)Glucuronidases.

Question 28

Tetracycline is an example of a drug that distributes in which tissue?

A)Bone and teeth
B)Blood
C)Brain
D)Fat

Question 29

Clinicians monitor the levels of certain drugs for different reasons.Which would not be an indication to monitor the level of a drug?

A)The drug is often taken in overdose.
B)The drug's effects are dangerous when the patient is noncompliant.
C)The drug has a high therapeutic window.
D)The drug's concentrations are not predictable from dosing parameters.

Question 30

Some people are poor metabolizers of certain drugs.In the case of clopidogrel,which is activated by the liver,which statement about poor metabolizers is true?

A)Poor metabolizers of clopidogrel do not efficiently convert it to its active form and thus may not receive its benefits.
B)Poor metabolizers may not metabolize clopidogrel and may instead develop toxic effects at therapeutic dosages.
C)The effects of clopidogrel are not changed in poor metabolizers.
D)Poor metabolizers require lower doses of clopidogrel in order to avoid toxic effects.

Question 31

Which term describes the ability of a drug to reach the systemic circulation after an oral dosage?

A)Extraction ratio
B)First pass
C)Bioavailability
D)Solubility

Question 32

Drugs enter the bloodstream from the GI tract and then enter the liver via the hepatic portal vein before entering the general circulation.This route allows the liver to metabolize the drugs into less active or inactive metabolites/drugs before they are distributed throughout the body.This effect is known as the:

A)Metabolic induction effect.
B)Enzyme saturation effect.
C)Steady state effect.
D)First-pass effect.

Question 33

The primary organ of drug metabolism is the:

A)Liver.
B)Kidney.
C)Skin.
D)Lungs.

Question 34

Which statement regarding urinary pH is false?

A)Urinary pH does not affect renal excretion of drugs.
B)Urinary pH can be manipulated to facilitate drug excretion.
C)In alkaline urine,acidic drugs are more readily ionized.
D)Ionized substances are more soluble in water and thus they are easily excreted in urine.Chapter 2.An Introduction to Pharmacodynamics and Pharmacokinetics

Question 35

The measure of the time it takes for half of a drug to be eliminated from the bloodstream is known as the:

A)ED50.
B)TD50.
C)Half-life.
D)Clearance.

Question 36

The pharmacologic term unbound or free drug refers to a drug that:

A)Is not bound to its specific receptors.
B)Is not bound to plasma proteins.
C)Cannot exert a pharmacologic effect.
D)Has been dissolved from its tablet state.

Question 37

Which combination is an example of a potentially toxic drug interaction with isoenzyme CYP2D6?

A)Quinidine and tricyclic antidepressants
B)Aspirin and clopidogrel
C)Nicotine and theophylline
D)Grapefruit juice and calcium channel blockers

Question 38

Which term refers to the pharmacokinetic process by which a drug moves from its site of administration,such as the muscle (given as an IM drug),into the circulatory system?

A)Distribution
B)Metabolism
C)Absorption
D)Elimination