Deck 3: Pharmacokinetics and Drug Dosing

Question 1

Drugs are excreted by the kidney___________.

A)mostly through glomerular filtration
B)if they are hydrophilic
C)if they are of small molecular weight
D)All of the above

Answer 1

All of the above

Question 2

All of the following statements involving first order kinetics are correct except ___________.

A)to achieve the clinical effect rapidly, a loading dose can be given
B)the volume of distribution plays a major role in determining the half-life of a drug
C)that doubling the dose of a drug will double the duration of drug action
D)that drug metabolism plays a major role in determining the half-life of a drug

Answer 2

that doubling the dose of a drug will double the duration of drug action

Question 3

Oral administration of drugs is often desired because _______________.

A)drugs are absorbed very rapidly from the GI tract
B)it is an efficient mode of administration for all drugs
C)it is the most convenient form of medication
D)100% of the drug is bioavailable

Answer 3

it is the most convenient form of medication

Question 4

Onset of action is fastest by ___________.

A)IV injection
B)oral administration
C)intramuscular injection
D)absorption is independent of the route of administration

Question 5

Metabolism or biotransformation of drugs ___________.

A)leads always to inactive metabolites
B)leads to more lipophilic metabolites
C)involves the p450 enzymes
D)affects the onset but not duration of action of drugs

Question 6

A drug has a half-life of 3 hours,which means ___________.

A)it takes 2 doses to achieve steady state drug levels in the body
B)it takes 21 hours for the body to be drug free after drug therapy has stopped
C)the drug should be taken every 3 hours
D)none of the above

Question 7

Weak acidic drugs acid-H ___________.

A)contain a NH₃⁺
B)occur mostly as the acid-H form at high pH
C)occur mostly as acid- form at low pH
D)have their ionization that can be determined by their pKa values

Question 8

First pass effect means that a drug ___________.

A)causes full clinical response the first time it passes through the target organ
B)penetrates very quickly through cell membranes
C)is very quickly absorbed from the GI tract
D)is quickly metabolized after absorption from the intestines by the liver

Question 9

Some drugs do not penetrate easily into the ___________.

A)brain
B)muscle
C)liver
D)heart

Question 10

Small lipid soluble or lipophilic drugs penetrate cell membranes by ___________.

A)passive diffusion
B)endocytosis
C)water filled channels
D)special transport systems

Question 11

All of the following may affect the duration of a drug's effects except _______________.

A)the rate of metabolism from active drugs to inactive metabolites
B)the rate of absorption into the bloodstream
C)the rate of excretion of inactive metabolites
D)the amount of protein binding

Question 12

All of the following statements concerning p450 enzymes are true except that they ___________.

A)are located in the endoplasmic reticulum of liver cells
B)consist of hundreds of isoenzymes
C)are classified using the abbreviation CYP
D)specifically metabolize drugs

Question 13

A weak base is mostly excreted ___________.

A)as the uncharged base
B)as the charged base
C)in an alkaline urine
D)none of the above

Question 14

100% bioavailability occurs with which one of the following drug administrations?

A)IV
B)Sublingual
C)Oral
D)Rectal

Question 15

Elimination of drugs ___________.

A)is enhanced at old age
B)is reduced markedly during cardiovascular diseases
C)is most frequently increased during multiple drug therapies
D)none of the above

Question 16

Phase I biotransformation reactions include all of the following except ___________.

A)oxidations
B)reductions
C)conjugations
D)hydrolyses

Question 17

Exercise ___________.

A)increases drug metabolism
B)decreases drug excretion
C)decreases absorption
D)and its effect on drug levels in the body are still uncertain

Question 18

The volume of distribution ___________.

A)estimates the amount of drug found in body tissues
B)is determined from blood level determinations
C)shows a high value when more drug is in body tissues compared to blood
D)All of the above

Question 19

The rate of passive diffusion ___________.

A)follows the law of mass action
B)is independent of molecular weight of the drug
C)depends mostly on the concentration gradient
D)All of the above

Question 20

First order kinetics means that a drug ___________.

A)leaves the body at a constant amount
B)has a half-life when half of the ingested drug has left the body
C)will achieve steady state levels in the body after 1-2 half lives
D)will leave the body completely after 4-5 half lives

Question 21

A person in shock would not respond to IM injections of medication because of which of the following reasons?

A)Diminished biliary functioning
B)Glomerular filtration impairments
C)Impaired liver metabolism
D)Impaired peripheral circulation