NR 565 FINAL EXAM – ADVANCED PHARMACOLOGY
FUNDAMENTALS 2026 COMPREHENSIVE PRACTICE
QUESTIONS WITH ANSWERS & RATIONALES
Question 1: A patient with a CYP2D6 poor metabolizer phenotype is
prescribed codeine for pain. What is the expected clinical outcome?
A) Increased analgesic effect due to higher codeine levels
B) Decreased analgesic effect due to inability to convert codeine to
morphine
C) No change in analgesic effect
D) Increased risk of respiratory depression
Correct Answer: B) Decreased analgesic effect due to inability to
convert codeine to morphine
Rationale: Codeine is a prodrug that requires conversion to morphine by
CYP2D6. Poor metabolizers (approximately 5-10% of the population) have
reduced or absent CYP2D6 activity, resulting in minimal conversion to
morphine and reduced analgesic effect. This is a classic example of
pharmacogenomics in clinical practice.
Question 2: A patient with a CYP2C19 poor metabolizer phenotype is
prescribed clopidogrel (Plavix) after a stent placement. What is the primary
concern?
A) Increased risk of bleeding
B) Decreased antiplatelet effect and increased risk of stent thrombosis
,C) Increased risk of hepatotoxicity
D) Decreased risk of adverse effects
Correct Answer: B) Decreased antiplatelet effect and increased risk of
stent thrombosis
Rationale: Clopidogrel is a prodrug that requires activation by CYP2C19. Poor
metabolizers have reduced conversion to the active metabolite, resulting in
decreased antiplatelet effect and increased risk of cardiovascular events,
including stent thrombosis. Alternative antiplatelet agents (e.g., ticagrelor)
may be preferred in these patients.
Question 3: Which of the following medications is affected by HLA-B*1502
allele status?
A) Warfarin
B) Carbamazepine
C) Clopidogrel
D) Codeine
Correct Answer: B) Carbamazepine
Rationale: HLA-B1502 allele is associated with an increased risk of Stevens-
Johnson syndrome and toxic epidermal necrolysis in patients taking
carbamazepine, especially in individuals of Asian descent (Han Chinese,
Thai, Malaysian). Genetic screening is recommended before starting
carbamazepine in at-risk populations. Other medications with HLA
associations include allopurinol and abacavir.*
Question 4: VKORC1 and CYP2C9 genetic testing is most relevant for which
medication?
,A) Clopidogrel
B) Warfarin
C) Codeine
D) Carbamazepine
Correct Answer: B) Warfarin
Rationale: VKORC1 (vitamin K epoxide reductase complex subunit 1) and
CYP2C9 polymorphisms affect warfarin metabolism and sensitivity. Patients
with certain variants require lower doses and are at increased risk of
bleeding. Genotype-guided dosing can improve the safety and efficacy of
warfarin therapy.
Question 5: A patient is a CYP2D6 ultra-rapid metabolizer. Which
medication would be most concerning?
A) Metoprolol
B) Codeine
C) Warfarin
D) Metformin
Correct Answer: B) Codeine
Rationale: CYP2D6 ultra-rapid metabolizers convert codeine to morphine
more rapidly and extensively, leading to higher morphine levels and
increased risk of toxicity, including respiratory depression. This is particularly
concerning in children and postoperative patients. The FDA has issued
warnings about codeine use in ultra-rapid metabolizers.
Question 6: Which of the following medications requires genetic testing
before use due to risk of serious skin reactions?
, A) Allopurinol
B) Carbamazepine
C) Abacavir
D) All of the above
Correct Answer: D) All of the above
Rationale: Allopurinol (HLA-B5801), carbamazepine (HLA-B1502), and
abacavir (HLA-B5701) all require genetic testing before use due to the risk
of serious skin reactions (Stevens-Johnson syndrome, toxic epidermal
necrolysis, or hypersensitivity reactions). HLA testing is recommended
before initiating these medications in at-risk populations.*
Question 7: Which of the following is a pharmacogenomic consideration
for simvastatin therapy?
A) SLCO1B1 polymorphism affecting risk of myopathy
B) CYP2D6 polymorphism affecting metabolism
C) VKORC1 polymorphism affecting dose response
D) HLA-B*5701 affecting hypersensitivity risk
Correct Answer: A) SLCO1B1 polymorphism affecting risk of myopathy
*Rationale: SLCO1B1 polymorphisms affect the hepatic uptake of statins,
including simvastatin. Patients with certain SLCO1B1 variants (particularly 5)
have increased risk of statin-induced myopathy. Genetic testing may help
guide statin selection and dosing to minimize this adverse effect.
Question 8: A patient being treated for HIV with abacavir should be tested
for which HLA allele before starting therapy?
FUNDAMENTALS 2026 COMPREHENSIVE PRACTICE
QUESTIONS WITH ANSWERS & RATIONALES
Question 1: A patient with a CYP2D6 poor metabolizer phenotype is
prescribed codeine for pain. What is the expected clinical outcome?
A) Increased analgesic effect due to higher codeine levels
B) Decreased analgesic effect due to inability to convert codeine to
morphine
C) No change in analgesic effect
D) Increased risk of respiratory depression
Correct Answer: B) Decreased analgesic effect due to inability to
convert codeine to morphine
Rationale: Codeine is a prodrug that requires conversion to morphine by
CYP2D6. Poor metabolizers (approximately 5-10% of the population) have
reduced or absent CYP2D6 activity, resulting in minimal conversion to
morphine and reduced analgesic effect. This is a classic example of
pharmacogenomics in clinical practice.
Question 2: A patient with a CYP2C19 poor metabolizer phenotype is
prescribed clopidogrel (Plavix) after a stent placement. What is the primary
concern?
A) Increased risk of bleeding
B) Decreased antiplatelet effect and increased risk of stent thrombosis
,C) Increased risk of hepatotoxicity
D) Decreased risk of adverse effects
Correct Answer: B) Decreased antiplatelet effect and increased risk of
stent thrombosis
Rationale: Clopidogrel is a prodrug that requires activation by CYP2C19. Poor
metabolizers have reduced conversion to the active metabolite, resulting in
decreased antiplatelet effect and increased risk of cardiovascular events,
including stent thrombosis. Alternative antiplatelet agents (e.g., ticagrelor)
may be preferred in these patients.
Question 3: Which of the following medications is affected by HLA-B*1502
allele status?
A) Warfarin
B) Carbamazepine
C) Clopidogrel
D) Codeine
Correct Answer: B) Carbamazepine
Rationale: HLA-B1502 allele is associated with an increased risk of Stevens-
Johnson syndrome and toxic epidermal necrolysis in patients taking
carbamazepine, especially in individuals of Asian descent (Han Chinese,
Thai, Malaysian). Genetic screening is recommended before starting
carbamazepine in at-risk populations. Other medications with HLA
associations include allopurinol and abacavir.*
Question 4: VKORC1 and CYP2C9 genetic testing is most relevant for which
medication?
,A) Clopidogrel
B) Warfarin
C) Codeine
D) Carbamazepine
Correct Answer: B) Warfarin
Rationale: VKORC1 (vitamin K epoxide reductase complex subunit 1) and
CYP2C9 polymorphisms affect warfarin metabolism and sensitivity. Patients
with certain variants require lower doses and are at increased risk of
bleeding. Genotype-guided dosing can improve the safety and efficacy of
warfarin therapy.
Question 5: A patient is a CYP2D6 ultra-rapid metabolizer. Which
medication would be most concerning?
A) Metoprolol
B) Codeine
C) Warfarin
D) Metformin
Correct Answer: B) Codeine
Rationale: CYP2D6 ultra-rapid metabolizers convert codeine to morphine
more rapidly and extensively, leading to higher morphine levels and
increased risk of toxicity, including respiratory depression. This is particularly
concerning in children and postoperative patients. The FDA has issued
warnings about codeine use in ultra-rapid metabolizers.
Question 6: Which of the following medications requires genetic testing
before use due to risk of serious skin reactions?
, A) Allopurinol
B) Carbamazepine
C) Abacavir
D) All of the above
Correct Answer: D) All of the above
Rationale: Allopurinol (HLA-B5801), carbamazepine (HLA-B1502), and
abacavir (HLA-B5701) all require genetic testing before use due to the risk
of serious skin reactions (Stevens-Johnson syndrome, toxic epidermal
necrolysis, or hypersensitivity reactions). HLA testing is recommended
before initiating these medications in at-risk populations.*
Question 7: Which of the following is a pharmacogenomic consideration
for simvastatin therapy?
A) SLCO1B1 polymorphism affecting risk of myopathy
B) CYP2D6 polymorphism affecting metabolism
C) VKORC1 polymorphism affecting dose response
D) HLA-B*5701 affecting hypersensitivity risk
Correct Answer: A) SLCO1B1 polymorphism affecting risk of myopathy
*Rationale: SLCO1B1 polymorphisms affect the hepatic uptake of statins,
including simvastatin. Patients with certain SLCO1B1 variants (particularly 5)
have increased risk of statin-induced myopathy. Genetic testing may help
guide statin selection and dosing to minimize this adverse effect.
Question 8: A patient being treated for HIV with abacavir should be tested
for which HLA allele before starting therapy?
