NURS6521: Advanced Pharmacology FINAL EXAM (Latest
2026/2027) – Walden University
SECTION 1: Pharmacokinetics, Pharmacodynamics, & Pharmacogenomics (Q1-Q15)
Q1: A 65-year-old patient with heart failure is prescribed digoxin 0.25 mg daily. The
nurse practitioner knows that digoxin has a narrow therapeutic index. Which laboratory
parameter is most critical to monitor to prevent toxicity?
A. Hemoglobin A1c
B. Serum digoxin level and renal function [CORRECT]
C. Thyroid stimulating hormone
D. Prostate-specific antigen
Correct Answer: B
Rationale: Digoxin has a narrow therapeutic index (0.5-2.0 ng/mL) with toxicity
occurring at levels >2.0 ng/mL; renal impairment reduces digoxin clearance, increasing
toxicity risk, making both serum levels and renal function essential monitoring
parameters. [100% VERIFIED – Walden NURS6521]
Q2: A patient taking warfarin for atrial fibrillation is started on amiodarone for
ventricular arrhythmias. The nurse practitioner anticipates which change in warfarin
dosing?
A. No dose adjustment is needed.
B. Decreased warfarin dose due to amiodarone's CYP2C9 and CYP3A4 inhibition
[CORRECT]
C. Increased warfarin dose due to amiodarone's enzyme induction.
D. Switch to aspirin due to contraindication.
Correct Answer: B
,Rationale: Amiodarone inhibits CYP2C9 and CYP3A4, reducing warfarin metabolism and
increasing INR/bleeding risk; the warfarin dose must be decreased by 30-50% with close
INR monitoring when amiodarone is initiated. [100% VERIFIED – Walden NURS6521]
Q3: A patient is a poor metabolizer of CYP2D6. Which medication would have reduced
analgesic efficacy in this patient?
A. Morphine
B. Codeine [CORRECT]
C. Oxycodone
D. Hydromorphone
Correct Answer: B
Rationale: Codeine is a prodrug requiring CYP2D6-mediated conversion to morphine for
analgesic effect; poor CYP2D6 metabolizers experience minimal analgesia due to
inadequate morphine production, necessitating alternative analgesics. [100% VERIFIED
– Walden NURS6521]
Q4: A patient on phenytoin for seizure disorder is started on carbamazepine. The nurse
practitioner recognizes that carbamazepine will affect phenytoin levels through which
mechanism?
A. Carbamazepine inhibits CYP3A4, increasing phenytoin levels.
B. Carbamazepine induces CYP3A4 and CYP2C9, potentially decreasing phenytoin
levels [CORRECT]
C. Carbamazepine has no effect on phenytoin metabolism.
D. Carbamazepine displaces phenytoin from albumin binding sites.
Correct Answer: B
Rationale: Carbamazepine is a potent CYP450 inducer (CYP3A4, CYP2C9) that
increases metabolism of substrates including phenytoin, potentially reducing phenytoin
levels and seizure control; therapeutic drug monitoring is essential when combining
these agents. [100% VERIFIED – Walden NURS6521]
,Q5: A patient taking atorvastatin drinks grapefruit juice daily. The nurse practitioner
counsels the patient that grapefruit juice inhibits which enzyme, increasing statin
toxicity risk?
A. CYP1A2
B. CYP2D6
C. CYP3A4 [CORRECT]
D. CYP2C19
Correct Answer: C
Rationale: Grapefruit juice inhibits intestinal CYP3A4, increasing bioavailability of
CYP3A4 substrates including atorvastatin, simvastatin, and lovastatin; this increases
myopathy and rhabdomyolysis risk, making pravastatin or fluvastatin (non-CYP3A4
substrates) preferable alternatives. [100% VERIFIED – Walden NURS6521]
Q6: A patient on fluoxetine for depression is started on tramadol for chronic pain. The
nurse practitioner is concerned about which potential interaction?
A. Increased tramadol metabolism reducing analgesia
B. Serotonin syndrome due to fluoxetine's CYP2D6 inhibition and serotonergic effects
[CORRECT]
C. Decreased fluoxetine absorption
D. Enhanced tramadol opioid effects
Correct Answer: B
Rationale: Fluoxetine is a potent CYP2D6 inhibitor and serotonergic agent; combining
with tramadol (which has serotonergic properties via SNRI mechanism and requires
CYP2D6 for active metabolite formation) increases serotonin syndrome risk and may
reduce analgesic efficacy. [100% VERIFIED – Walden NURS6521]
Q7: A patient receives a loading dose of phenytoin followed by a maintenance dose. The
purpose of the loading dose is to:
A. Reduce the drug's half-life
B. Achieve therapeutic plasma concentration more rapidly [CORRECT]
C. Decrease the volume of distribution
D. Eliminate the need for therapeutic drug monitoring
, Correct Answer: B
Rationale: Loading doses rapidly achieve therapeutic plasma concentrations in
situations requiring immediate effect (status epilepticus, arrhythmias); maintenance
doses then sustain steady-state levels (achieved after 4-5 half-lives) without loading
dose delays. [100% VERIFIED – Walden NURS6521]
Q8: A patient with Asian ancestry is prescribed carbamazepine for bipolar disorder.
Which pharmacogenomic testing should be obtained before initiation?
A. CYP2D6 genotyping
B. HLA-B1502 testing [CORRECT]
C. G6PD deficiency testing
D. CYP2C19 genotyping
Correct Answer: B
Rationale: HLA-B1502 allele is strongly associated with Stevens-Johnson syndrome and
toxic epidermal necrolysis in Asian populations treated with carbamazepine; FDA
recommends testing in patients of Asian ancestry before initiating therapy. [100%
VERIFIED – Walden NURS6521]
Q9: A patient with G6PD deficiency is prescribed trimethoprim-sulfamethoxazole for a
urinary tract infection. The nurse practitioner recognizes this combination places the
patient at risk for:
A. Nephrogenic diabetes insipidus
B. Hemolytic anemia [CORRECT]
C. Hyperthyroidism
D. Agranulocytosis
Correct Answer: B
Rationale: G6PD deficiency impairs the hexose monophosphate shunt, reducing NADPH
and glutathione production; oxidative stress from sulfonamides (and dapsone,
2026/2027) – Walden University
SECTION 1: Pharmacokinetics, Pharmacodynamics, & Pharmacogenomics (Q1-Q15)
Q1: A 65-year-old patient with heart failure is prescribed digoxin 0.25 mg daily. The
nurse practitioner knows that digoxin has a narrow therapeutic index. Which laboratory
parameter is most critical to monitor to prevent toxicity?
A. Hemoglobin A1c
B. Serum digoxin level and renal function [CORRECT]
C. Thyroid stimulating hormone
D. Prostate-specific antigen
Correct Answer: B
Rationale: Digoxin has a narrow therapeutic index (0.5-2.0 ng/mL) with toxicity
occurring at levels >2.0 ng/mL; renal impairment reduces digoxin clearance, increasing
toxicity risk, making both serum levels and renal function essential monitoring
parameters. [100% VERIFIED – Walden NURS6521]
Q2: A patient taking warfarin for atrial fibrillation is started on amiodarone for
ventricular arrhythmias. The nurse practitioner anticipates which change in warfarin
dosing?
A. No dose adjustment is needed.
B. Decreased warfarin dose due to amiodarone's CYP2C9 and CYP3A4 inhibition
[CORRECT]
C. Increased warfarin dose due to amiodarone's enzyme induction.
D. Switch to aspirin due to contraindication.
Correct Answer: B
,Rationale: Amiodarone inhibits CYP2C9 and CYP3A4, reducing warfarin metabolism and
increasing INR/bleeding risk; the warfarin dose must be decreased by 30-50% with close
INR monitoring when amiodarone is initiated. [100% VERIFIED – Walden NURS6521]
Q3: A patient is a poor metabolizer of CYP2D6. Which medication would have reduced
analgesic efficacy in this patient?
A. Morphine
B. Codeine [CORRECT]
C. Oxycodone
D. Hydromorphone
Correct Answer: B
Rationale: Codeine is a prodrug requiring CYP2D6-mediated conversion to morphine for
analgesic effect; poor CYP2D6 metabolizers experience minimal analgesia due to
inadequate morphine production, necessitating alternative analgesics. [100% VERIFIED
– Walden NURS6521]
Q4: A patient on phenytoin for seizure disorder is started on carbamazepine. The nurse
practitioner recognizes that carbamazepine will affect phenytoin levels through which
mechanism?
A. Carbamazepine inhibits CYP3A4, increasing phenytoin levels.
B. Carbamazepine induces CYP3A4 and CYP2C9, potentially decreasing phenytoin
levels [CORRECT]
C. Carbamazepine has no effect on phenytoin metabolism.
D. Carbamazepine displaces phenytoin from albumin binding sites.
Correct Answer: B
Rationale: Carbamazepine is a potent CYP450 inducer (CYP3A4, CYP2C9) that
increases metabolism of substrates including phenytoin, potentially reducing phenytoin
levels and seizure control; therapeutic drug monitoring is essential when combining
these agents. [100% VERIFIED – Walden NURS6521]
,Q5: A patient taking atorvastatin drinks grapefruit juice daily. The nurse practitioner
counsels the patient that grapefruit juice inhibits which enzyme, increasing statin
toxicity risk?
A. CYP1A2
B. CYP2D6
C. CYP3A4 [CORRECT]
D. CYP2C19
Correct Answer: C
Rationale: Grapefruit juice inhibits intestinal CYP3A4, increasing bioavailability of
CYP3A4 substrates including atorvastatin, simvastatin, and lovastatin; this increases
myopathy and rhabdomyolysis risk, making pravastatin or fluvastatin (non-CYP3A4
substrates) preferable alternatives. [100% VERIFIED – Walden NURS6521]
Q6: A patient on fluoxetine for depression is started on tramadol for chronic pain. The
nurse practitioner is concerned about which potential interaction?
A. Increased tramadol metabolism reducing analgesia
B. Serotonin syndrome due to fluoxetine's CYP2D6 inhibition and serotonergic effects
[CORRECT]
C. Decreased fluoxetine absorption
D. Enhanced tramadol opioid effects
Correct Answer: B
Rationale: Fluoxetine is a potent CYP2D6 inhibitor and serotonergic agent; combining
with tramadol (which has serotonergic properties via SNRI mechanism and requires
CYP2D6 for active metabolite formation) increases serotonin syndrome risk and may
reduce analgesic efficacy. [100% VERIFIED – Walden NURS6521]
Q7: A patient receives a loading dose of phenytoin followed by a maintenance dose. The
purpose of the loading dose is to:
A. Reduce the drug's half-life
B. Achieve therapeutic plasma concentration more rapidly [CORRECT]
C. Decrease the volume of distribution
D. Eliminate the need for therapeutic drug monitoring
, Correct Answer: B
Rationale: Loading doses rapidly achieve therapeutic plasma concentrations in
situations requiring immediate effect (status epilepticus, arrhythmias); maintenance
doses then sustain steady-state levels (achieved after 4-5 half-lives) without loading
dose delays. [100% VERIFIED – Walden NURS6521]
Q8: A patient with Asian ancestry is prescribed carbamazepine for bipolar disorder.
Which pharmacogenomic testing should be obtained before initiation?
A. CYP2D6 genotyping
B. HLA-B1502 testing [CORRECT]
C. G6PD deficiency testing
D. CYP2C19 genotyping
Correct Answer: B
Rationale: HLA-B1502 allele is strongly associated with Stevens-Johnson syndrome and
toxic epidermal necrolysis in Asian populations treated with carbamazepine; FDA
recommends testing in patients of Asian ancestry before initiating therapy. [100%
VERIFIED – Walden NURS6521]
Q9: A patient with G6PD deficiency is prescribed trimethoprim-sulfamethoxazole for a
urinary tract infection. The nurse practitioner recognizes this combination places the
patient at risk for:
A. Nephrogenic diabetes insipidus
B. Hemolytic anemia [CORRECT]
C. Hyperthyroidism
D. Agranulocytosis
Correct Answer: B
Rationale: G6PD deficiency impairs the hexose monophosphate shunt, reducing NADPH
and glutathione production; oxidative stress from sulfonamides (and dapsone,
