old mult. choice questions Flashcards
Drug induced liver injury is a significant problem for many drugs already in clinical use, as well as new drugs under development Which of the following efflux transporters is most often involved in drug-induced cholestasis?
a. P-glycoprotein
b. multi drug resistance associated protein
c. breast cancer resistance protein
d. organic anion transporting polypeptide
e. bile salt export protein
e. bile salt export protein
Which one of the following cytochrome P-450 enzymes plays the most prominent role in first pass metabolism drugs? a. CYP 1A2 b. CYP 2D6 c. CYP 2E! d. CYP 3A4 e. CYP 2C19
d. CYP 3A4
Quinidine interacts with digoxin by which of the following mechanism?
a. inhibition of CYP 2D6
b. inhibition of P-glycoprotein
c. inhibition of CYP 3A4
d. induction of P-glycoprotein
e. induction of CYP 2D6
b. inhibition of P-glycoprotein
An individual who is overly sensitive to the effects of codeine may result from:
a. expression of a a non synonymous CYP 2D6 SNP
b. expression of a synonymous CYP 2D6 SNP
c. expression of multiple copies of the CYP 2D6 gene
d. a deletion in the CYP 2D6 gene
e. expression of a non synonymous CYP 2C9 SNP
c. expression of multiple copies of the CYP 2D6 gene
Rifampin induces the effectiveness of oral contraceptives by which of the following?
a. induction of CYP 1A2
b. induction of CYP 3A4
c. induction of CYP 2C9
d. induction of OATP
e. Induction of P-gp
b. induction of CYP 3A4
Which of the following SSRI’s are adversely affected by induction of CYP 2D6?
a. fluoxetine
b. paroxetine
c. citalopram
d. fluvoxamine
e. all of the above
f. none of the above
f. none of the above – There are no known inducers of CYP 2D6
Which of the following nuclear receptors is responsible for up regulating transcription of the CYP 3A4 gene? a. steroid xenobiotic receptor b. farnesoid X receptor c. constitutive androstane receptor d aryl hydrocarbon receptor e. vitamin E receptor
a. steroid xenobiotic receptor
Transplant recipients immunosuppressed with cyclosporine are at risk for graft rejection when ingesting which herbal supplement?
a. ginseng
b. St. John’s wort
c. echinacea
d. saw palmetto
e. ginkgo biloba
b. St. John’s wort
Which of the following statements is true regarding the interaction between penicillin and probenecid?
a. probenecid reduces the hepatic clearance of penicillin
b. probenecid decreases the half life of penicillin
c. probenecid increases the renal clearance of penicillin
d. probenecid inhibits the renal uptake transporter OAT
e. probenecid inhibits CYP 1A2
d. probenecid inhibits the renal uptake transporter OAT
Fruit juices can often affect the bioavailability of drugs when ingested concomitantly. Which combination of juice and drug will result in an increase in oral bioavailability?
a. grapefruit juice and felodipine
b. grapefruit juice and chlorzoxazone
c. orange juice and fexofenadine
d. orange juice and caffeine
e. cranberry juice and midazolam
a. grapefruit juice and felodipine
A patient has been receiving codeine for pain after tooth extraction is not experiencing any therapeutic benefit (i.e. pain relief). If this patient;s lack of response is because of an inability to metabolize codeine to the active moiety morphine, a homozygous genetic mutation in which one of the following genes is most likely responsible?
a. CYP 1A2
b. CYP 2C9
c. CYP 2D6
d. CYP 2C19
e. CYP 3A4
c. CYP 2D6
Grapefruit juice will significantly increase the oral bioavailability of which of the following drugs?
a. indinavir (CYP 3A4 substrate, F=0.8)
b. quinidine (CYP 3A4/P-gp substrate, F=0.8)
c. fexofenadine (OATP substrate, F=0.2)
d. nisoldipine (CYP 3A4 substrate, F=0.1)
e. amlodipine (CYP 3A4 substrate, F=0.7)
d. nisoldipine (CYP 3A4 substrate, F=0.1)
A patient with DVT is being treated with warfarin at a standard dose of 5 mg/day. One week later, the patient presents with an intracerebral hemorrhage and the international normalized ratio is 11. The patient is genotyped and found to have a genetic mutation in the enzyme responsible for the metabolism of S-warfarin. The pharmacogenetics of which one of the following enzymes has been associated with adverse clinical outcomes and warfarin maintenance dose requirements?
a. CYP 1A2
b. CYP 2C9
c. CYP 2D6
d. CYP 3A4
e. CYP 2C19
b. CYP 2C9
Which one of the following transporters plays the most prominent role in first pass drug elimination?
a. OATP
b. OCTP
c. MRP2
d. BSEP
e. P-gp
e. P-gp
What effect does rifampin have on the pharmacokinetics of drugs whose metabolism is predominantly mediated by CYP 2D6?
a. has little effect on unbound steady state concentrations
b. significantly increases unbound stead state concentration
c. significantly decreases unbound steady state concentrations
d. significantly increases elimination half life
e. significantly decreases hepatic blood flow
a. has little effect on unbound steady state concentrations
A renal transplant patient receiving tacrolimus (CYP 3A4/P-gp substrate) for immunosuppression develops a systemic Candida albicans infection. Which of the following azalea antifungals is least likely to produce elected levels of tacrolimus and subsequent nephrotoxicity?
a. fluconazole
b. ketoconazole
c. itraconazole
d. miconazole
e. voriconazole
a. fluconazole
Which SSRI is associated with the fewest number of significant drug interactions?
a. citalopram
b. fluvoxamine
c. fluoxetine
d. paroxetine
e. venlafaxine
a. Citalopram
In general, which of the following pharmacokinetic parameters has the least impact on average unbound steady state concentrations?
a. clearance
b. bioavailability
c. dose
d. plasma protein binding
e. apparent volume of distribution
e. apparent volume of distribution
- Individuals homozygous for the CYP 2D6*3 allele will likely exhibit toxicity after chronic dosing of which of the following drugs?
a. quinidine
b. amitriptyline
c. codeine
d. warfarin
e. phenytoin
b. amitriptyline
- Which of the following is not an inhibitor of CYP 2D6?
a. quinidine
b. fluoxetine
c. paroxetine
d. amiodarone
e. fluvoxamine
e. fluvoxamine