NURS 5334 Prep Exam Quiz 2 With Advanced
Pharmacology Practice 150 Questions,
Answers, and Rationales
Exam
### Question 1
A patient with end-stage renal disease (eGFR <15 mL/min) is
prescribed a medication that is 70% renally excreted. The nurse
practitioner should anticipate:
A) Increasing the dose by 50%
B) Decreasing the dosing frequency
C) Changing to a prodrug
D) Adding a diuretic to enhance excretion
**Correct Answer: B**
**Rationale:** Reduced renal clearance leads to drug accumulation
in patients with renal impairment. Decreasing the dosing frequency
maintains therapeutic levels without causing toxicity. Increasing the
dose would worsen toxicity, and prodrug conversion may actually be
impaired in renal failure. Diuretics do not enhance excretion of drugs
with significant renal clearance .
### Question 2
,Which cytochrome P450 enzyme is most commonly involved in
clinically significant drug-drug interactions?
A) CYP1A2
B) CYP2D6
C) CYP3A4
D) CYP2C9
**Correct Answer: C**
**Rationale:** CYP3A4 metabolizes approximately 50% of marketed
drugs, including statins, calcium channel blockers, and
benzodiazepines. It is highly susceptible to inhibition (by grapefruit
juice, ketoconazole) and induction (by rifampin, carbamazepine),
making it the most common source of clinically significant drug
interactions .
### Question 3
A drug with a high first-pass effect is given orally. The NP understands
that:
A) The drug will have increased bioavailability
B) The drug must be given via a non-oral route to avoid extensive
hepatic metabolism
C) Gastric pH will alter absorption significantly
D) Protein binding will be decreased
,**Correct Answer: B**
**Rationale:** High first-pass effect means the liver metabolizes a
significant portion of the drug before it reaches systemic circulation.
Intravenous, intramuscular, or sublingual routes bypass portal
circulation and avoid first-pass metabolism, increasing bioavailability .
### Question 4
A drug with a high therapeutic index is considered:
A) More likely to cause toxicity
B) Safer than a drug with a low therapeutic index
C) Less effective than a drug with a low therapeutic index
D) More likely to cause allergic reactions
**Correct Answer: B**
**Rationale:** The therapeutic index is the ratio between the toxic
dose and the therapeutic dose. A high therapeutic index indicates a
wide margin of safety, meaning the drug is safer and less likely to
cause toxicity. Drugs with a narrow therapeutic index (e.g., digoxin,
lithium, warfarin) require careful monitoring .
### Question 5
What is the difference between an agonist and an antagonist?
, A) Agonists block receptors; antagonists activate them
B) Agonists activate receptors; antagonists block them
C) Both activate receptors but through different mechanisms
D) Both block receptors but have different binding affinities
**Correct Answer: B**
**Rationale:** Agonists bind to and activate receptors, producing a
biological response. Antagonists bind to receptors but do not activate
them; instead, they block the action of agonists. Partial agonists
produce a submaximal response regardless of concentration .
### Question 6
After one half-life, what percentage of the original drug dose remains
in the body?
A) 25%
B) 50%
C) 75%
D) 90%
**Correct Answer: B**
Pharmacology Practice 150 Questions,
Answers, and Rationales
Exam
### Question 1
A patient with end-stage renal disease (eGFR <15 mL/min) is
prescribed a medication that is 70% renally excreted. The nurse
practitioner should anticipate:
A) Increasing the dose by 50%
B) Decreasing the dosing frequency
C) Changing to a prodrug
D) Adding a diuretic to enhance excretion
**Correct Answer: B**
**Rationale:** Reduced renal clearance leads to drug accumulation
in patients with renal impairment. Decreasing the dosing frequency
maintains therapeutic levels without causing toxicity. Increasing the
dose would worsen toxicity, and prodrug conversion may actually be
impaired in renal failure. Diuretics do not enhance excretion of drugs
with significant renal clearance .
### Question 2
,Which cytochrome P450 enzyme is most commonly involved in
clinically significant drug-drug interactions?
A) CYP1A2
B) CYP2D6
C) CYP3A4
D) CYP2C9
**Correct Answer: C**
**Rationale:** CYP3A4 metabolizes approximately 50% of marketed
drugs, including statins, calcium channel blockers, and
benzodiazepines. It is highly susceptible to inhibition (by grapefruit
juice, ketoconazole) and induction (by rifampin, carbamazepine),
making it the most common source of clinically significant drug
interactions .
### Question 3
A drug with a high first-pass effect is given orally. The NP understands
that:
A) The drug will have increased bioavailability
B) The drug must be given via a non-oral route to avoid extensive
hepatic metabolism
C) Gastric pH will alter absorption significantly
D) Protein binding will be decreased
,**Correct Answer: B**
**Rationale:** High first-pass effect means the liver metabolizes a
significant portion of the drug before it reaches systemic circulation.
Intravenous, intramuscular, or sublingual routes bypass portal
circulation and avoid first-pass metabolism, increasing bioavailability .
### Question 4
A drug with a high therapeutic index is considered:
A) More likely to cause toxicity
B) Safer than a drug with a low therapeutic index
C) Less effective than a drug with a low therapeutic index
D) More likely to cause allergic reactions
**Correct Answer: B**
**Rationale:** The therapeutic index is the ratio between the toxic
dose and the therapeutic dose. A high therapeutic index indicates a
wide margin of safety, meaning the drug is safer and less likely to
cause toxicity. Drugs with a narrow therapeutic index (e.g., digoxin,
lithium, warfarin) require careful monitoring .
### Question 5
What is the difference between an agonist and an antagonist?
, A) Agonists block receptors; antagonists activate them
B) Agonists activate receptors; antagonists block them
C) Both activate receptors but through different mechanisms
D) Both block receptors but have different binding affinities
**Correct Answer: B**
**Rationale:** Agonists bind to and activate receptors, producing a
biological response. Antagonists bind to receptors but do not activate
them; instead, they block the action of agonists. Partial agonists
produce a submaximal response regardless of concentration .
### Question 6
After one half-life, what percentage of the original drug dose remains
in the body?
A) 25%
B) 50%
C) 75%
D) 90%
**Correct Answer: B**
