Prodigy Pharmacokinetics

Question 1

Which is the single most important enzyme, accounting for 40-45 percent of all mediated drug metabolism?

Answer 1

CYP3A4

Question 2

After intravenous administration of fentanyl, there is an initial rapid increase in plasma concentration of the drug followed by a rapid decline in plasma administration. This initial, rapid decline is due primarily to

Answer 2

redistribution to highly-perfused organs

Question 3

Once injected, the plasma concentration of an opioid such as fentanyl _______

Answer 3

rises rapidly.

Question 4

Shortly after this initial rise, the plasma concentration rapidly

Answer 4

decreases as the drug is distributed into the highly perfused organs such as the brain, liver, and kidneys. A second, slower decrease in the plasma concentration occurs as the drug distributes into the less well-perfused tissues such as the muscles and adipose tissue.

Question 5

A protein binds to a cell membrane receptor, causing it to open and allow the passage of substances into the cell. This is an example of a

Answer 5

ligand-gated receptor

Question 6

A ligand-gated receptor is triggered by the

Answer 6

binding of a chemical to the receptor. When this occurs, the receptor’s shape alters causing the channel to open. This allows the passage of specific substances through the channel.

Question 7

Which drug exhibits the classic drug-drug interaction associated with serotonin syndrome when combined with MAOIs?

Answer 7

Meperidine

Question 8

The classic drug interaction associated with serotonin syndrome is the combination of meperidine with.

Answer 8

MAOIs

Question 9

Phenylpiperidines including (4) associated with interactions with MAOI and serotonin

Answer 9

fentanyl, methadone, and tramadol and methylene blue have also been associated.

Question 10

The term that describes the amount of drug within the body as a whole compared to the amount of the drug in the bloodstream is the

Answer 10

The volume of distribution is a number that describes the amount of drug in the body compared to how much is actually in the bloodstream.

Question 11

Vd: It is calculated as

Answer 11

Vd = Amount of drug in body/Plasma concentation of the drug. It actually describes an apparent volume.

Question 12

If a large amount of a drug has been administered and only a small amount of the drug appears in the plasma, the drug is said to have a ____Vd

Answer 12

have a large volume of distribution.

Question 13

What term refers to the dose of a drug required to produce a given effect in 50 percent of subjects

Answer 13

Potency (ED 50)

Question 14

The only process that does not involve the cytochrome P450 pathway is

Answer 14

Hydrolysis

Question 15

Cytochrome P450 enzymes are involved in

Answer 15

oxidation, reduction, and conjugation reactions.

Question 16

The only metabolic pathway in which CYP 450 they are not present is

Answer 16

hydrolysis, which typically occurs outside of the liver.

Question 17

Drugs such as(4) undergo hydrolysis.

Answer 17

remifentanil, esmolol, succinylcholine, and ester local anesthetics

Question 18

Which of the following measurements predicts the time it takes for 50% of a drug to be eliminated from the central compartment when a continuous infusion is discontinued?

Answer 18

Context sensitive half time

Question 19

The steady-state plasma concentration corresponds to the

Answer 19

steady concentration at the site of action and is determined by a concentration-response curve

Question 20

Which term refers to the theoretical volume of blood from which a drug is completely and irreversibly removed in a unit of time?

Answer 20

Elimination clearance

Question 21

The most important factor determining the rate of diffusion of a drug across a membrane is

Answer 21

Concentration gradient accross the membrane

Question 22

What is hepatic enzyme induction?

Answer 22

If liver enzymes are exposed to particular compounds or drugs over a period of time, they will increase their activity, resulting in an increased ability to metabolize the drugs.

Question 23

A chemical that can bind with a protein to form a new complex is a

Answer 23

Ligand

Question 24

The primary function of phase II conjugation reactions are to make the molecule more

Answer 24

Water-soluble

Question 25

Remifentanil exhibits a _____ volume of distribution than fentanyl due to a(n) _____ clearance.

Answer 25

smaller, increased

Question 26

Drugs such as fentanyl that are

Answer 26

highly lipophilic and exhibit low protein-binding exhibit a high volume of distribution.

Question 27

Opioids such as remifentanil and alfentanil exhibit a

Answer 27

smaller volume of distribution due to increased protein binding and a faster clearance

Question 28

Most drug metabolism is performed by microsomal enzymes in the smooth endoplasmic reticulum of the

Answer 28

Liver cells

Question 29

The vessel-poor group is comprised of bone, ligament, and cartilage, accounts for

Answer 29

20% of the body mass, and receives a negligible amount (0%) of the cardiac output.

Question 30

The vessel-poor group is comprised of

Answer 30

bone, ligament, and cartilage, accounts for

Question 31

The muscle group is comprised of muscle and skin. It accounts for______% body mass and receives ___% of the Cardiac output

Answer 31

50% of the body mass and receives 19% of the cardiac output.

Question 32

Vessel RICH GROUP It comprises ____%of the body mass but receives 75% of the cardiac output.

Answer 32

10%

Question 33

The maximum duration that a single transdermal medication patch would be effective is about____days? Why?

Answer 33

7 days; Because the skin sloughs and regenerates about every 7 days, the maximum duration for a single transdermal application is about 7 days.

Question 34

A drug is being administered by continuous infusion, and its plasma concentration is now constant. The drug is said to be in

Answer 34

Steady state

Question 35

Ideally, a medication used for a transdermal application has (weigh)

Answer 35

a molecular weight less than 1000 daltons

Question 36

Ideally, a medication used for a transdermal application has (ph and lipid solubility)

Answer 36

pH between 5-9 in an aqueous solution

Question 37

Ideally, a medication used for a transdermal application has (daily requirements)

Answer 37

less than 10 mg

Question 38

Hepatic clearance is the product of the hepatic blood flow and the drug’s

Answer 38

hepatic extraction ratio

Question 39

Which of the following is a Phase II reaction?

Answer 39

conjugation and synthesis reactions.

Question 40

Which anesthetic intervention is typically avoided in patients undergoing a large hepatic resection?

Answer 40

Epidural catheter placement

Question 41

Even if the preoperative coagulation studies were normal, patients undergoing liver resection can exhibit an

Answer 41

abnormal INR and platelet count postoperatively.The effect peaks on postop day 1 or 2 and typically resolves by about 5 days postop. Because of the alteration in coagulation studies, many practitioners avoid epidural catheter placement.

Question 42

The diffusion of a drug across a membrane from an area of higher concentration to an area of lower concentration without the expenditure of energy is

Answer 42

Passive transport

Question 43

Erythromycin administration in patients taking theophylline can lead to

Answer 43

theophylline toxicity. erythromycin can inhibit the metabolism of theophylline and potentially lead to theophylline toxicity.

Question 44

What is pharmacokinetics?

Answer 44

Pharmacokinetics, or what the body does to the drug can be remembered with the ADME mnemonic, which stands for absorption, distribution, metabolism, and excretion of the drug.

Question 45

In opioids with a small volume of distribution, the termination of the analgesic effect is primarily due to

Answer 45

Clearance of the drug

Question 46

Determining the safety margin of a drug requires that you know data about the effective dose of the drug and

Answer 46

the Lethal dose

Question 47

Select two inducers of hepatic drug metabolism.

Answer 47

Rifampin

Phenytoin

Question 48

Name some inducers of CYP450

Answer 48

carbamazepine, ethanol, glucocorticoids, phenobarbital, phenytoin, rifampin, St. John’s Wort, and tamoxifen.

Question 49

What determines the duration of action of an irreversible antagonist?

Answer 49

Receptor regeneration

Question 50

When you administer a bolus dose of a drug intravenously, which tissue would have an increase in the tissue concentration of the drug first?

Answer 50

Liver

Question 51

The plasma half-life of a drug is inversely proportional to its

Answer 51

rate of clearance

Question 52

The percent of a drug that the liver can clear as it passes through it is referred to as the

Answer 52

hepatic extraction ratio

Question 53

Which of the following terms refers to compounds that bind to receptors without producing any changes in cellular function?

Answer 53

Antagonists

Question 54

Which drug or drug class is an inhibitor of hepatic drug metabolism?

Answer 54

azole antifungal drugs, cimetidine, disulfiram, grapefruit juice, macrolide antibiotics, protease inhibitors, quinidine, SSRIs.

Question 55

One of the advantages of transdermal medication over other routes is that it

Answer 55

provides a more consistent plasma concentratio

Question 56

transdermal site A common side effect

Answer 56

can be rash or erythema at the application site.

Question 57

Hepatic enzyme induction will result in a reduction in the ____ of a drug.

Answer 57

half-life

Question 58

Which of the following medication administration routes can undergo first-pass hepatic metabolism?

Answer 58

oral / rectal

Question 59

In opioids with a high volume of distribution, the decrease in plasma concentration and termination of the analgesic effect is due primarily to

Answer 59

Redistribution

Question 60

Which Phase 1 reaction is characterized by reactions that remove electrons from a molecule?

Answer 60

Oxidation

Question 61

Select two common treatments for moderate to severe serotonin syndrome.

Answer 61

Chlorpromazine

Cyproheptadine