NR 568 Final Exam Prep 2026 | 200 Advanced Pharmacology
Questions with Answers & Rationales | Nursing Study Guide
SECTION A: PHARMACOKINETICS & PHARMACODYNAMICS (Questions 1–40)
1. A 70-year-old patient with heart failure is started on digoxin. Which age-related change in
pharmacokinetics most increases the risk of toxicity?
A. Decreased renal clearance of digoxin
B. Increased hepatic first-pass metabolism
C. Increased volume of distribution for water-soluble drugs
D. Enhanced glomerular filtration rate
Answer: A
Explanation: Renal clearance declines with age, reducing digoxin elimination; dose adjustment based on
renal function and monitoring of levels is essential.
2. A patient with a genetic polymorphism resulting in CYP2D6 poor metabolizer phenotype is prescribed
codeine for pain. What is the most likely outcome?
A. Little to no analgesic effect due to inability to convert codeine to morphine
B. Increased risk of respiratory depression from rapid conversion to morphine
C. Prolonged half-life of codeine but normal analgesia
D. Increased risk of serotonin syndrome
Answer: A
Explanation: Codeine is a prodrug requiring CYP2D6 to convert to active morphine; poor metabolizers
have reduced analgesia.
3. A patient is receiving a drug that is a weak base (pKa 8.5). Which of the following would increase its
renal excretion?
A. Alkalinizing the urine (increasing pH)
B. Acidifying the urine (decreasing pH)
C. Increasing urine flow rate only
,D. Decreasing urine flow rate
Answer: B
Explanation: Weak bases are ionized (and less reabsorbed) in acidic urine; acidification traps the drug in
urine, enhancing excretion.
4. A patient with hepatic cirrhosis has a reduced ability to metabolize drugs via phase I reactions. Which
drug would be most affected?
A. Lorazepam (primarily phase II glucuronidation)
B. Phenytoin (primarily phase I oxidation)
C. Acetaminophen at therapeutic doses (phase II)
D. Morphine (phase II)
Answer: B
Explanation: Phenytoin undergoes extensive hepatic oxidation (CYP450); cirrhosis impairs phase I more
than phase II, leading to accumulation and toxicity.
5. A patient is started on a drug with a narrow therapeutic index. The nurse practitioner orders
therapeutic drug monitoring. Which principle best justifies this?
A. Small changes in dose or clearance can lead to toxicity or treatment failure
B. All drugs require monitoring regardless of index
C. The drug has a wide safety margin
D. Monitoring is only needed for intravenous drugs
Answer: A
Explanation: Narrow therapeutic index drugs (e.g., warfarin, phenytoin, digoxin) have small margins
between efficacy and toxicity, requiring monitoring.
6. A patient is taking a drug that is a substrate of P-glycoprotein (P-gp). Which co-administered drug
could increase the oral bioavailability of this substrate?
A. A P-gp inhibitor (e.g., verapamil)
B. A P-gp inducer (e.g., rifampin)
C. A CYP3A4 inducer
D. A gastric acid reducer
,Answer: A
Explanation: P-gp pumps drugs back into the intestinal lumen; inhibiting P-gp increases absorption and
bioavailability.
7. A patient with renal impairment (CrCl 25 mL/min) requires a drug that is 90% renally excreted. The
recommended dosing adjustment is to:
A. Reduce the dose or prolong the dosing interval proportionally to CrCl
B. Increase the dose to achieve therapeutic levels
C. No adjustment needed because renal impairment does not affect excretion
D. Double the loading dose
Answer: A
Explanation: For renally cleared drugs, dose reduction or interval prolongation based on CrCl is standard
to prevent accumulation and toxicity.
8. A patient has been on a drug with a half-life of 24 hours. Approximately how long will it take to reach
steady state?
A. 5 days (120 hours)
B. 24 hours
C. 12 hours
D. 10 days
Answer: A
Explanation: Steady state is reached after approximately 5 half-lives; 5 × 24 = 120 hours (5 days).
9. Which of the following drug interactions is most likely to be caused by competition for plasma protein
binding?
A. Increased free fraction of warfarin when given with sulfonamides
B. Inhibition of CYP3A4 by ketoconazole
C. Induction of CYP2C9 by rifampin
D. Decreased renal clearance of digoxin by verapamil
Answer: A
, Explanation: Sulfonamides displace warfarin from albumin, increasing free warfarin and bleeding risk;
this is a protein-binding interaction.
10. A patient is prescribed a drug that is a high extraction ratio drug. Which statement about its oral
bioavailability is correct?
A. It is highly dependent on hepatic blood flow
B. It is independent of hepatic blood flow
C. It is primarily determined by protein binding
D. It is always 100% regardless of liver function
Answer: A
Explanation: High extraction ratio drugs (e.g., propranolol, lidocaine) have bioavailability limited by
hepatic blood flow; changes in flow alter bioavailability.
11. A patient with severe heart failure is receiving an intravenous infusion of a drug that is eliminated
primarily by hepatic metabolism. The nurse practitioner anticipates that the drug’s clearance will be:
A. Reduced due to decreased hepatic blood flow
B. Increased due to increased cardiac output
C. Unchanged because liver function is normal
D. Reduced only if cirrhosis is present
Answer: A
Explanation: Heart failure reduces hepatic blood flow, decreasing clearance of high extraction ratio
drugs.
12. A patient is switched from an immediate-release formulation to an extended-release formulation of
the same drug. Which pharmacokinetic parameter is most likely to change?
A. Time to peak concentration (Tmax)
B. Volume of distribution (Vd)
C. Bioavailability (F) if same total dose
D. Elimination half-life
Answer: A
Questions with Answers & Rationales | Nursing Study Guide
SECTION A: PHARMACOKINETICS & PHARMACODYNAMICS (Questions 1–40)
1. A 70-year-old patient with heart failure is started on digoxin. Which age-related change in
pharmacokinetics most increases the risk of toxicity?
A. Decreased renal clearance of digoxin
B. Increased hepatic first-pass metabolism
C. Increased volume of distribution for water-soluble drugs
D. Enhanced glomerular filtration rate
Answer: A
Explanation: Renal clearance declines with age, reducing digoxin elimination; dose adjustment based on
renal function and monitoring of levels is essential.
2. A patient with a genetic polymorphism resulting in CYP2D6 poor metabolizer phenotype is prescribed
codeine for pain. What is the most likely outcome?
A. Little to no analgesic effect due to inability to convert codeine to morphine
B. Increased risk of respiratory depression from rapid conversion to morphine
C. Prolonged half-life of codeine but normal analgesia
D. Increased risk of serotonin syndrome
Answer: A
Explanation: Codeine is a prodrug requiring CYP2D6 to convert to active morphine; poor metabolizers
have reduced analgesia.
3. A patient is receiving a drug that is a weak base (pKa 8.5). Which of the following would increase its
renal excretion?
A. Alkalinizing the urine (increasing pH)
B. Acidifying the urine (decreasing pH)
C. Increasing urine flow rate only
,D. Decreasing urine flow rate
Answer: B
Explanation: Weak bases are ionized (and less reabsorbed) in acidic urine; acidification traps the drug in
urine, enhancing excretion.
4. A patient with hepatic cirrhosis has a reduced ability to metabolize drugs via phase I reactions. Which
drug would be most affected?
A. Lorazepam (primarily phase II glucuronidation)
B. Phenytoin (primarily phase I oxidation)
C. Acetaminophen at therapeutic doses (phase II)
D. Morphine (phase II)
Answer: B
Explanation: Phenytoin undergoes extensive hepatic oxidation (CYP450); cirrhosis impairs phase I more
than phase II, leading to accumulation and toxicity.
5. A patient is started on a drug with a narrow therapeutic index. The nurse practitioner orders
therapeutic drug monitoring. Which principle best justifies this?
A. Small changes in dose or clearance can lead to toxicity or treatment failure
B. All drugs require monitoring regardless of index
C. The drug has a wide safety margin
D. Monitoring is only needed for intravenous drugs
Answer: A
Explanation: Narrow therapeutic index drugs (e.g., warfarin, phenytoin, digoxin) have small margins
between efficacy and toxicity, requiring monitoring.
6. A patient is taking a drug that is a substrate of P-glycoprotein (P-gp). Which co-administered drug
could increase the oral bioavailability of this substrate?
A. A P-gp inhibitor (e.g., verapamil)
B. A P-gp inducer (e.g., rifampin)
C. A CYP3A4 inducer
D. A gastric acid reducer
,Answer: A
Explanation: P-gp pumps drugs back into the intestinal lumen; inhibiting P-gp increases absorption and
bioavailability.
7. A patient with renal impairment (CrCl 25 mL/min) requires a drug that is 90% renally excreted. The
recommended dosing adjustment is to:
A. Reduce the dose or prolong the dosing interval proportionally to CrCl
B. Increase the dose to achieve therapeutic levels
C. No adjustment needed because renal impairment does not affect excretion
D. Double the loading dose
Answer: A
Explanation: For renally cleared drugs, dose reduction or interval prolongation based on CrCl is standard
to prevent accumulation and toxicity.
8. A patient has been on a drug with a half-life of 24 hours. Approximately how long will it take to reach
steady state?
A. 5 days (120 hours)
B. 24 hours
C. 12 hours
D. 10 days
Answer: A
Explanation: Steady state is reached after approximately 5 half-lives; 5 × 24 = 120 hours (5 days).
9. Which of the following drug interactions is most likely to be caused by competition for plasma protein
binding?
A. Increased free fraction of warfarin when given with sulfonamides
B. Inhibition of CYP3A4 by ketoconazole
C. Induction of CYP2C9 by rifampin
D. Decreased renal clearance of digoxin by verapamil
Answer: A
, Explanation: Sulfonamides displace warfarin from albumin, increasing free warfarin and bleeding risk;
this is a protein-binding interaction.
10. A patient is prescribed a drug that is a high extraction ratio drug. Which statement about its oral
bioavailability is correct?
A. It is highly dependent on hepatic blood flow
B. It is independent of hepatic blood flow
C. It is primarily determined by protein binding
D. It is always 100% regardless of liver function
Answer: A
Explanation: High extraction ratio drugs (e.g., propranolol, lidocaine) have bioavailability limited by
hepatic blood flow; changes in flow alter bioavailability.
11. A patient with severe heart failure is receiving an intravenous infusion of a drug that is eliminated
primarily by hepatic metabolism. The nurse practitioner anticipates that the drug’s clearance will be:
A. Reduced due to decreased hepatic blood flow
B. Increased due to increased cardiac output
C. Unchanged because liver function is normal
D. Reduced only if cirrhosis is present
Answer: A
Explanation: Heart failure reduces hepatic blood flow, decreasing clearance of high extraction ratio
drugs.
12. A patient is switched from an immediate-release formulation to an extended-release formulation of
the same drug. Which pharmacokinetic parameter is most likely to change?
A. Time to peak concentration (Tmax)
B. Volume of distribution (Vd)
C. Bioavailability (F) if same total dose
D. Elimination half-life
Answer: A
