Pharmacotherapuetics

Question 1

What is a therapeutic range?

Answer 1

If a drug has a high therapeutic range, it will have varied plasma concentrations for a given dose in different people

Question 2

A therapeutic range is an example of the ____________ differences in drugs.

Answer 2

pharmacokinetic

Question 3

___________ differences are when a drug is present at a given plasma concentration but has different effects in different people.

Answer 3

Pharmacodynamic

Question 4

T/F: Nitrous oxide is less effective at high altitude.

Answer 4

True

Question 5

What is the cheese effect?

Answer 5

If someone is taking MAO inhibiters for depression, they will not have MAO to metabolize the tyramine in cheese and red wine. This excess tyramine can lead to hypertensive crisis

Question 6

What is CYP3A4 and why is grapefruit juice often avoided when taking certain drugs?

Answer 6

CYP3A4 is responsible for metabolism of 60% of drugs; grapefruit juice (not orange juice) reduces expression of CYP3A4

Question 7

What is tolerance?

Answer 7

Decreased responsiveness to drug upon repeated or continuous administration

Question 8

What is the difference between pharmacokinetic tolerance and pharmacodynamic tolerance?

Answer 8

PK: effective drug concentration is diminished

PD: Physio response is diminished

Question 9

_________ is a special kind of tolerance where there is rapid loss of response after drug administration.

Answer 9

Tachyphylaxis

Question 10

What are three methods of inducing pharmacokinetic tolerance?

Answer 10

1. Induction of metabolizing enzymes in liver
2. Induction of transport proteins
3. Immune tolerance (antibodies against drug)

Question 11

T/F: You can fix pharmacokinetic tolerance by adjusting the dose.

Answer 11

True

Question 12

Which type of tolerance is often seen with CNS drugs?

Answer 12

Pharmacodynamic tolerance

Question 13

What are two major mechanisms for pharmacodynamic tolerance?

Answer 13

1. Down regulation of receptors

2. Impairment of signal transduction

Question 14

Tyramine increases heart rate and BP by promoting release of norepinephrine. However, the NE stores are quickly depleted and effects are lost. Which type of tolerance is this?

Answer 14

Acute tolerance - tachyphylaxis

Question 15

T/F: Tolerance can be induced by changes in cellular distribution.

Answer 15

True

E.g. Overexpression of P-glycoprotein which removes things from the cell (including drugs)

Question 16

The opposite of drug tolerance is __________ to a drug.

Answer 16

sensitization

*seen with cocaine

Question 17

What is an extension effect?

Answer 17

A dosage effect where if a patient has too much of a response it will cause problems

Question 18

What types of drugs often experience negative extension effects?

Answer 18

Blood thinners (Warfarin)

WIll be thinning the blood just a little too much - must lower the dosage

Question 19

_____________ are effects that occur rarely and unpredictably amongst the population.

Answer 19

Idiosyncratic rxns

Question 20

Procaine toxicity due to low serum cholinesterase levels is an example of an ___________.

Answer 20

idiosyncratic rxns

Question 21

T/F: Dose is important in avoiding an allergic response.

Answer 21

False

Question 22

T/F: Patients will have an allergic response the first time they are given a certain drug.

Answer 22

False

Question 23

What percentage of the population is allergic to penicillins or sulfonamides?

Answer 23

5%

Question 24

T/F: It is common for drugs that are lipids to be allergenic.

Answer 24

False

Proteins

Question 25

T/F: Antigenic potential of drugs increases with exposure to heat/sunlight.

Answer 25

True

Question 26

What are the four types of drug allergy responses?

Answer 26

Type I: Anaphylactic Type II: Cytotoxic Type III: Immune complex Type IV: Cell-mediated

Question 27

Which antibodies and cells are associated with type I allergic response?

Answer 27

IgE will bring about Mast Cells for an immediate rxn

Question 28

How long does a type II response take?

Answer 28

several hours to days

Question 29

What antibodies mediate the type II allergic response?

Answer 29

IgG, IgM complement will attack and cause tissue damage

Question 30

What mediates a type III allergic response?

Answer 30

Mediated by IgG and neutrophils

Question 31

What mediates a type IV allergic response?

Answer 31

T cells; takes days to occur with chronic exposure

Question 32

T/F: Drugs taken orally are more likely to cause allergies than drugs taken topically.

Answer 32

False Orally less allergenic than topically

Question 33

T/F: It is okay to give pregnant women class X drugs.

Answer 33

False Class A and B are definitely okay Class C and D are questionable

Question 34

T/F: Class C drugs have shown fetal abnormalities in human studies.

Answer 34

False No adequate human studies, animal studies lacking or have shown risk