Exam II Enzyme Inhibition/Induction

Question 1

Less drugs bound to plasma proteins results in higher free concentrations in cells and more rapid ______ from body

Answer 1

Clearance

Question 2

P-gp is inhibited by what drugs?

Answer 2

Ketoconzacole

Cyclosporin

Question 3

P-gp is induced by what drugs?

Answer 3

rifampicin and carbamazepine

Question 4

what inhibits OATP1A1 and OATP2B1?

Answer 4

apple juice, orange juice, and grapefruit juice

Question 5

speaking in terms of pharmacokinetics, inducing metabolism of a drug causes? (graph)

Answer 5

inc rate of inactivation and elimination, dec AUC, and lower drug efficacy

Question 6

speaking in terms of pharmacokinetics, inhibiting drug metabolism of a drug causes? (graph)

Answer 6

reduces deactivation and elimination, inc AUC, possible toxicity

Question 7

according to FDA dec of at least what % in AUC is relevant induction, and increase of at least ___-fold in AUC is relevant inhibition?

Answer 7

20, 1.25

Question 8

what drug(s) inhibits CYP2D6 in tamoxifen pathway where tamoxifen wont work if also taken?

Answer 8

paroxetine, fluoxetine

Question 9

what enzyme metabolizes codeine to morphine? if inhibited, how does this affect drug? why?

Answer 9

CYP2D6, reduces efficacy of codeine because codeine is inactive. if it cannot be metabolized to active form (morphine) it wont be effective

Question 10

can CYP2D6 be induced?

Answer 10

no

Question 11

St john’s wort induces what enzyme?

Answer 11

CYP3A4

Question 12

piperine inhibits what enzymes?

Answer 12

CYP3A4, CYP2C9

Question 13

primary environmental cause of induction?

Answer 13

smoke

Question 14

grapefruit can irreversibly inhibit which two enzymes?

Answer 14

CYP3A4 and OATPs