NR 546 Advanced Pharmacology | Midterm Examination Chamberlain University
NR 546 MIDTERM EXAM
Advanced Pharmacology
Actual Exam Questions and Correct Detailed Answers | A Grade
Chamberlain University · Graduate Nursing Program · 100 Questions
Section 1: Advanced Pharmacokinetics and Pharmacodynamics (Q1 - Q15)
(Absorption, Distribution, Metabolism, Excretion, Receptors, & Dose-Response)
Q1. A 62-year-old female is started on oral propranolol 40 mg twice daily for hypertension. Compared with
intravenous propranolol, the oral route produces significantly lower systemic drug concentrations despite
complete absorption. Which pharmacokinetic principle best explains this finding?
A. Reduced gastric emptying prolongs absorption time
B. Extensive first-pass hepatic metabolism reduces bioavailability [CORRECT]
C. High plasma protein binding limits free drug distribution
D. P-glycoprotein efflux in the GI tract blocks absorption
Correct Answer: B
Rationale: Propranolol is a high-extraction-ratio drug that undergoes extensive hepatic first-pass metabolism, reducing
oral bioavailability to approximately 25-30%. Although GI absorption is nearly complete, the liver metabolizes most of
the drug before it reaches systemic circulation. This is why oral doses are substantially higher than IV doses. The other
options do not explain the discrepancy between complete absorption and low systemic availability.
Q2. An NP is prescribing a drug with high first-pass metabolism to a patient with cirrhosis. Which change in
dosing is most appropriate compared with a patient with normal hepatic function?
A. Increase oral dose due to enhanced metabolism
B. Decrease oral dose because first-pass metabolism is reduced [CORRECT]
C. Switch to intramuscular route to bypass the liver
D. Maintain dose; cirrhosis affects only Phase II reactions
Correct Answer: B
Rationale: Cirrhosis reduces hepatic blood flow and impairs first-pass metabolism, increasing oral bioavailability of
high-extraction drugs (e.g., propranolol, morphine, verapamil). The dose should be decreased to avoid toxicity. IM
route still enters systemic circulation but bypasses portal circulation only partially; the safer action is dose reduction.
Phase I metabolism (CYP450) is generally more affected than Phase II in cirrhosis.
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,NR 546 Advanced Pharmacology | Midterm Examination Chamberlain University
Q3. A drug has a volume of distribution (Vd) of 4 L/kg in a 70-kg patient. Which interpretation is most
accurate?
A. The drug is confined primarily to the plasma compartment
B. The drug distributes mainly to extracellular fluid
C. The drug is highly tissue-bound and accumulates in peripheral compartments [CORRECT]
D. The drug has low lipid solubility and renal excretion
Correct Answer: C
Rationale: A Vd of 4 L/kg (280 L total) far exceeds total body water (~0.6 L/kg), indicating extensive tissue
distribution and sequestration, typical of highly lipophilic or tissue-bound drugs such as amiodarone, digoxin, or
tricyclic antidepressants. Plasma-confined drugs have Vd ~0.05 L/kg, extracellular drugs ~0.2 L/kg. High Vd means
plasma levels remain low and hemodialysis is ineffective for removal.
Q4. A patient on warfarin (highly protein-bound, 99%) is started on sulfamethoxazole-trimethoprim, which
also binds albumin. Three days later, the INR is supratherapeutic. What is the primary mechanism of this
interaction?
A. Sulfamethoxazole induces CYP2C9, increasing warfarin clearance
B. Sulfamethoxazole displaces warfarin from albumin, transiently raising free warfarin [CORRECT]
C. Sulfamethoxazole inhibits warfarin metabolism via CYP3A4
D. Trimethoprim enhances GI absorption of warfarin
Correct Answer: B
Rationale: Sulfamethoxazole is highly albumin-bound and displaces warfarin from binding sites, transiently increasing
free warfarin. However, sustained INR elevation occurs because sulfamethoxazole also inhibits CYP2C9, the primary
warfarin-metabolizing enzyme. The displacement alone causes only transient elevation because free drug is also
available for clearance; the CYP2C9 inhibition produces the clinically significant sustained interaction.
Q5. Which of the following medications, when initiated in a patient chronically taking phenytoin, is most
likely to cause decreased phenytoin levels and potential loss of seizure control?
A. Clarithromycin
B. Fluconazole
C. Carbamazepine [CORRECT]
D. Amiodarone
Correct Answer: C
Rationale: Carbamazepine is a potent CYP3A4 and CYP2C9 inducer that increases phenytoin metabolism, lowering
phenytoin concentrations. Clarithromycin, fluconazole, and amiodarone are all CYP inhibitors that would increase
phenytoin levels and risk toxicity. Enzyme induction typically takes 1-2 weeks for full effect, and phenytoin levels
should be monitored with dose adjustment when inducers are added or removed.
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,NR 546 Advanced Pharmacology | Midterm Examination Chamberlain University
Q6. A patient stabilized on theophylline develops pneumonia and is started on ciprofloxacin. Three days later,
the patient experiences nausea, tachycardia, and tremors. The theophylline level is 28 mcg/mL (therapeutic
10-20). What is the most likely mechanism?
A. Ciprofloxacin induces CYP1A2, increasing theophylline clearance
B. Ciprofloxacin inhibits CYP1A2, reducing theophylline clearance [CORRECT]
C. Theophylline displaces ciprofloxacin from protein binding
D. The pneumonia reduces hepatic blood flow independently
Correct Answer: B
Rationale: Ciprofloxacin is a potent CYP1A2 inhibitor. Theophylline is metabolized primarily by CYP1A2, so
concurrent administration reduces theophylline clearance, causing accumulation and toxicity. Theophylline has a
narrow therapeutic index, so CYP1A2 inhibitors (ciprofloxacin, erythromycin, verapamil) require dose reduction or
selection of alternative antibiotics such as azithromycin, which minimally affects CYP1A2.
Q7. A patient is prescribed a beta-1 selective antagonist for hypertension. Compared with a non-selective beta
antagonist, this selectivity confers which pharmacodynamic advantage at therapeutic doses?
A. Greater reduction in myocardial contractility
B. Lower risk of bronchoconstriction in patients with asthma [CORRECT]
C. Increased efficacy in heart failure with reduced ejection fraction
D. Greater suppression of renin release
Correct Answer: B
Rationale: Beta-1 selective antagonists (metoprolol, atenolol) preferentially block cardiac beta-1 receptors at
therapeutic doses, sparing pulmonary beta-2 receptors and reducing bronchoconstriction risk in asthma/COPD.
Selectivity is dose-dependent and lost at higher doses. The other effects (contractility reduction, HFrEF efficacy, renin
suppression) are class effects of all beta-blockers and not advantages of selectivity.
Q8. Drug X has an EC50 of 5 mg and Emax of 80%, while Drug Y has an EC50 of 20 mg and Emax of 95%,
both acting on the same receptor. Which statement is correct?
A. Drug X is more potent; Drug Y has higher efficacy [CORRECT]
B. Drug X is more potent and has higher efficacy
C. Drug Y is more potent; Drug X has higher efficacy
D. Drug Y is more potent and has higher efficacy
Correct Answer: A
Rationale: Potency is reflected by EC50: lower EC50 means greater potency. Drug X (EC50 5 mg) is more potent than
Drug Y (EC50 20 mg). Efficacy is reflected by Emax: Drug Y (95%) has higher efficacy than Drug X (80%). A drug
can be more potent yet less efficacious, which is why clinical decisions consider both parameters along with safety,
onset, and patient factors.
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Q9. A 70-kg patient requires a loading dose of phenytoin to rapidly achieve a target level of 15 mg/L. The
drug's volume of distribution is 0.7 L/kg. Assuming 100% bioavailability IV, what loading dose is most
appropriate?
A. 105 mg
B. 350 mg
C. 735 mg [CORRECT]
D. 1050 mg
Correct Answer: C
Rationale: Loading dose = (Vd x target concentration) / bioavailability = (0.7 L/kg x 70 kg) x 15 mg/L = 49 L x 15
mg/L = 735 mg. The standard IV phenytoin loading dose is approximately 15-20 mg/kg, consistent with this
calculation. Administration should be no faster than 50 mg/min to avoid cardiovascular depression, and cardiac
monitoring is required.
Q10. A patient starts a medication with a half-life of 24 hours. Without a loading dose, approximately how
long will it take to reach approximately 94% of steady-state concentration?
A. 24 hours
B. 48 hours
C. 72 hours
D. 120 hours [CORRECT]
Correct Answer: D
Rationale: Steady state is reached in approximately 4-5 half-lives. Four half-lives = 94% of steady state. For a 24-hour
half-life drug, 4 x 24 = 96 hours, and 5 x 24 = 120 hours (97%). The closest answer is 120 hours. If rapid therapeutic
effect is needed before steady state, a loading dose can be administered to achieve target concentration immediately.
Q11. A patient with CKD stage 4 (eGFR 22 mL/min/1.73m2) requires vancomycin for MRSA bacteremia.
Which dosing adjustment is most appropriate?
A. Standard dose with no monitoring required
B. Loading dose 25-30 mg/kg, then extended-interval dosing guided by trough levels [CORRECT]
C. Reduce frequency only; maintain standard 1 g every 12 hours
D. Switch to oral vancomycin to avoid nephrotoxicity
Correct Answer: B
Rationale: Vancomycin is primarily renally cleared; in severe CKD, a loading dose of 25-30 mg/kg achieves
therapeutic troughs, followed by extended-interval dosing (often every 24-72 hours or longer) with trough monitoring
targeting 15-20 mcg/mL for serious MRSA infections. Oral vancomycin is not systemically absorbed and is only used
for C. difficile colitis. Standard dosing risks accumulation and nephrotoxicity.
Confidential - For NR 546 Exam Preparation Page 4
NR 546 MIDTERM EXAM
Advanced Pharmacology
Actual Exam Questions and Correct Detailed Answers | A Grade
Chamberlain University · Graduate Nursing Program · 100 Questions
Section 1: Advanced Pharmacokinetics and Pharmacodynamics (Q1 - Q15)
(Absorption, Distribution, Metabolism, Excretion, Receptors, & Dose-Response)
Q1. A 62-year-old female is started on oral propranolol 40 mg twice daily for hypertension. Compared with
intravenous propranolol, the oral route produces significantly lower systemic drug concentrations despite
complete absorption. Which pharmacokinetic principle best explains this finding?
A. Reduced gastric emptying prolongs absorption time
B. Extensive first-pass hepatic metabolism reduces bioavailability [CORRECT]
C. High plasma protein binding limits free drug distribution
D. P-glycoprotein efflux in the GI tract blocks absorption
Correct Answer: B
Rationale: Propranolol is a high-extraction-ratio drug that undergoes extensive hepatic first-pass metabolism, reducing
oral bioavailability to approximately 25-30%. Although GI absorption is nearly complete, the liver metabolizes most of
the drug before it reaches systemic circulation. This is why oral doses are substantially higher than IV doses. The other
options do not explain the discrepancy between complete absorption and low systemic availability.
Q2. An NP is prescribing a drug with high first-pass metabolism to a patient with cirrhosis. Which change in
dosing is most appropriate compared with a patient with normal hepatic function?
A. Increase oral dose due to enhanced metabolism
B. Decrease oral dose because first-pass metabolism is reduced [CORRECT]
C. Switch to intramuscular route to bypass the liver
D. Maintain dose; cirrhosis affects only Phase II reactions
Correct Answer: B
Rationale: Cirrhosis reduces hepatic blood flow and impairs first-pass metabolism, increasing oral bioavailability of
high-extraction drugs (e.g., propranolol, morphine, verapamil). The dose should be decreased to avoid toxicity. IM
route still enters systemic circulation but bypasses portal circulation only partially; the safer action is dose reduction.
Phase I metabolism (CYP450) is generally more affected than Phase II in cirrhosis.
Confidential - For NR 546 Exam Preparation Page 1
,NR 546 Advanced Pharmacology | Midterm Examination Chamberlain University
Q3. A drug has a volume of distribution (Vd) of 4 L/kg in a 70-kg patient. Which interpretation is most
accurate?
A. The drug is confined primarily to the plasma compartment
B. The drug distributes mainly to extracellular fluid
C. The drug is highly tissue-bound and accumulates in peripheral compartments [CORRECT]
D. The drug has low lipid solubility and renal excretion
Correct Answer: C
Rationale: A Vd of 4 L/kg (280 L total) far exceeds total body water (~0.6 L/kg), indicating extensive tissue
distribution and sequestration, typical of highly lipophilic or tissue-bound drugs such as amiodarone, digoxin, or
tricyclic antidepressants. Plasma-confined drugs have Vd ~0.05 L/kg, extracellular drugs ~0.2 L/kg. High Vd means
plasma levels remain low and hemodialysis is ineffective for removal.
Q4. A patient on warfarin (highly protein-bound, 99%) is started on sulfamethoxazole-trimethoprim, which
also binds albumin. Three days later, the INR is supratherapeutic. What is the primary mechanism of this
interaction?
A. Sulfamethoxazole induces CYP2C9, increasing warfarin clearance
B. Sulfamethoxazole displaces warfarin from albumin, transiently raising free warfarin [CORRECT]
C. Sulfamethoxazole inhibits warfarin metabolism via CYP3A4
D. Trimethoprim enhances GI absorption of warfarin
Correct Answer: B
Rationale: Sulfamethoxazole is highly albumin-bound and displaces warfarin from binding sites, transiently increasing
free warfarin. However, sustained INR elevation occurs because sulfamethoxazole also inhibits CYP2C9, the primary
warfarin-metabolizing enzyme. The displacement alone causes only transient elevation because free drug is also
available for clearance; the CYP2C9 inhibition produces the clinically significant sustained interaction.
Q5. Which of the following medications, when initiated in a patient chronically taking phenytoin, is most
likely to cause decreased phenytoin levels and potential loss of seizure control?
A. Clarithromycin
B. Fluconazole
C. Carbamazepine [CORRECT]
D. Amiodarone
Correct Answer: C
Rationale: Carbamazepine is a potent CYP3A4 and CYP2C9 inducer that increases phenytoin metabolism, lowering
phenytoin concentrations. Clarithromycin, fluconazole, and amiodarone are all CYP inhibitors that would increase
phenytoin levels and risk toxicity. Enzyme induction typically takes 1-2 weeks for full effect, and phenytoin levels
should be monitored with dose adjustment when inducers are added or removed.
Confidential - For NR 546 Exam Preparation Page 2
,NR 546 Advanced Pharmacology | Midterm Examination Chamberlain University
Q6. A patient stabilized on theophylline develops pneumonia and is started on ciprofloxacin. Three days later,
the patient experiences nausea, tachycardia, and tremors. The theophylline level is 28 mcg/mL (therapeutic
10-20). What is the most likely mechanism?
A. Ciprofloxacin induces CYP1A2, increasing theophylline clearance
B. Ciprofloxacin inhibits CYP1A2, reducing theophylline clearance [CORRECT]
C. Theophylline displaces ciprofloxacin from protein binding
D. The pneumonia reduces hepatic blood flow independently
Correct Answer: B
Rationale: Ciprofloxacin is a potent CYP1A2 inhibitor. Theophylline is metabolized primarily by CYP1A2, so
concurrent administration reduces theophylline clearance, causing accumulation and toxicity. Theophylline has a
narrow therapeutic index, so CYP1A2 inhibitors (ciprofloxacin, erythromycin, verapamil) require dose reduction or
selection of alternative antibiotics such as azithromycin, which minimally affects CYP1A2.
Q7. A patient is prescribed a beta-1 selective antagonist for hypertension. Compared with a non-selective beta
antagonist, this selectivity confers which pharmacodynamic advantage at therapeutic doses?
A. Greater reduction in myocardial contractility
B. Lower risk of bronchoconstriction in patients with asthma [CORRECT]
C. Increased efficacy in heart failure with reduced ejection fraction
D. Greater suppression of renin release
Correct Answer: B
Rationale: Beta-1 selective antagonists (metoprolol, atenolol) preferentially block cardiac beta-1 receptors at
therapeutic doses, sparing pulmonary beta-2 receptors and reducing bronchoconstriction risk in asthma/COPD.
Selectivity is dose-dependent and lost at higher doses. The other effects (contractility reduction, HFrEF efficacy, renin
suppression) are class effects of all beta-blockers and not advantages of selectivity.
Q8. Drug X has an EC50 of 5 mg and Emax of 80%, while Drug Y has an EC50 of 20 mg and Emax of 95%,
both acting on the same receptor. Which statement is correct?
A. Drug X is more potent; Drug Y has higher efficacy [CORRECT]
B. Drug X is more potent and has higher efficacy
C. Drug Y is more potent; Drug X has higher efficacy
D. Drug Y is more potent and has higher efficacy
Correct Answer: A
Rationale: Potency is reflected by EC50: lower EC50 means greater potency. Drug X (EC50 5 mg) is more potent than
Drug Y (EC50 20 mg). Efficacy is reflected by Emax: Drug Y (95%) has higher efficacy than Drug X (80%). A drug
can be more potent yet less efficacious, which is why clinical decisions consider both parameters along with safety,
onset, and patient factors.
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Q9. A 70-kg patient requires a loading dose of phenytoin to rapidly achieve a target level of 15 mg/L. The
drug's volume of distribution is 0.7 L/kg. Assuming 100% bioavailability IV, what loading dose is most
appropriate?
A. 105 mg
B. 350 mg
C. 735 mg [CORRECT]
D. 1050 mg
Correct Answer: C
Rationale: Loading dose = (Vd x target concentration) / bioavailability = (0.7 L/kg x 70 kg) x 15 mg/L = 49 L x 15
mg/L = 735 mg. The standard IV phenytoin loading dose is approximately 15-20 mg/kg, consistent with this
calculation. Administration should be no faster than 50 mg/min to avoid cardiovascular depression, and cardiac
monitoring is required.
Q10. A patient starts a medication with a half-life of 24 hours. Without a loading dose, approximately how
long will it take to reach approximately 94% of steady-state concentration?
A. 24 hours
B. 48 hours
C. 72 hours
D. 120 hours [CORRECT]
Correct Answer: D
Rationale: Steady state is reached in approximately 4-5 half-lives. Four half-lives = 94% of steady state. For a 24-hour
half-life drug, 4 x 24 = 96 hours, and 5 x 24 = 120 hours (97%). The closest answer is 120 hours. If rapid therapeutic
effect is needed before steady state, a loading dose can be administered to achieve target concentration immediately.
Q11. A patient with CKD stage 4 (eGFR 22 mL/min/1.73m2) requires vancomycin for MRSA bacteremia.
Which dosing adjustment is most appropriate?
A. Standard dose with no monitoring required
B. Loading dose 25-30 mg/kg, then extended-interval dosing guided by trough levels [CORRECT]
C. Reduce frequency only; maintain standard 1 g every 12 hours
D. Switch to oral vancomycin to avoid nephrotoxicity
Correct Answer: B
Rationale: Vancomycin is primarily renally cleared; in severe CKD, a loading dose of 25-30 mg/kg achieves
therapeutic troughs, followed by extended-interval dosing (often every 24-72 hours or longer) with trough monitoring
targeting 15-20 mcg/mL for serious MRSA infections. Oral vancomycin is not systemically absorbed and is only used
for C. difficile colitis. Standard dosing risks accumulation and nephrotoxicity.
Confidential - For NR 546 Exam Preparation Page 4
