2 VERSIONS NSG 5240 Advanced Pharmacology
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Version 1 (Questions 1-100)
SECTION 1: PHARMACOKINETICS & PHARMACODYNAMICS (Questions 1-40)
1. A patient with severe hypoalbuminemia is receiving a highly protein-bound
medication. The nurse anticipates that the free (unbound) drug concentration will be:
A) Decreased, requiring a higher dose
B) Increased, requiring a lower dose
C) Unchanged because binding does not affect free drug levels
D) Decreased because the drug will accumulate in adipose tissue
Answer: B) Increased, requiring a lower dose
Explanation: Hypoalbuminemia reduces available protein binding sites, resulting in a higher
fraction of unbound (free) drug. Free drug is pharmacologically active. Increased free drug
can lead to toxicity, so a lower dose may be needed .
2. A drug that follows zero-order kinetics (e.g., phenytoin at therapeutic doses)
exhibits which characteristic?
,A) A constant fraction of the drug is eliminated per unit time
B) A constant amount of the drug is eliminated per unit time
C) Elimination rate is directly proportional to plasma concentration
D) Half-life remains constant regardless of dose
Answer: B) A constant amount of the drug is eliminated per unit time
Explanation: Zero-order kinetics means the elimination rate is constant regardless of
concentration (e.g., 10 mg/hour). A constant fraction (e.g., 10% per hour) describes first-
order kinetics. Zero-order drugs have a half-life that increases with dose, and small dose
changes can cause large concentration changes .
3. A patient is started on a drug with a half-life of 24 hours. Approximately how many
days will it take to reach steady-state plasma concentrations?
A) 1 day
B) 3 days
C) 5 days
D) 7 days
Answer: C) 5 days
Explanation: Steady state is reached after approximately 4–5 half-lives. With a 24-hour half-
life, steady state occurs in 4–5 days. 7 days would be more than 5 half-lives, but 5 days is
the closest accurate estimate .
,4. Cytochrome P450 (CYP) enzyme induction results in:
A) Decreased metabolism of certain drugs, leading to increased drug levels
B) Increased metabolism of certain drugs, leading to decreased drug levels
C) No change in drug metabolism
D) Decreased renal excretion of drugs
Answer: B) Increased metabolism of certain drugs, leading to decreased drug levels
Explanation: Enzyme induction (e.g., by rifampin, phenytoin, carbamazepine) increases
synthesis or activity of CYP isoenzymes, accelerating metabolism of substrates. This
reduces plasma concentrations and may reduce therapeutic effect .
5. A patient taking warfarin is started on rifampin, a strong CYP2C9 and CYP3A4
inducer. The nurse expects the INR to:
A) Increase, requiring warfarin dose reduction
B) Decrease, requiring warfarin dose increase
C) Remain unchanged
D) Fluctuate unpredictably
Answer: B) Decrease, requiring warfarin dose increase
Explanation: Rifampin induces CYP2C9 (major warfarin metabolizer), increasing warfarin
clearance and lowering INR. The patient will need a higher warfarin dose to maintain
therapeutic INR, and the INR will drop when rifampin is added .
, 6. Grapefruit juice inhibits which cytochrome P450 isoenzyme, leading to increased
levels of certain drugs?
A) CYP2D6
B) CYP3A4
C) CYP1A2
D) CYP2C9
Answer: B) CYP3A4
Explanation: Grapefruit juice irreversibly inhibits intestinal CYP3A4, reducing first-pass
metabolism of substrates (e.g., statins, calcium channel blockers, cyclosporine). This
increases bioavailability and risk of toxicity .
7. A patient has a genetic variant that causes decreased activity of CYP2D6 (poor
metabolizer phenotype). When prescribed codeine, the patient is at risk for:
A) Increased morphine production and toxicity
B) Decreased morphine production and reduced analgesia
C) No change in codeine effect
D) Increased risk of serotonin syndrome
Answer: B) Decreased morphine production and reduced analgesia
Explanation: Codeine is a prodrug that requires O-demethylation via CYP2D6 to form
morphine, the active analgesic. Poor metabolizers produce little morphine, leading to
inadequate pain relief. Ultra-rapid metabolizers are at risk for morphine toxicity .
Midterm Practice Exam New Edition: South College
Questions With Answers and Explanations Latest
Update This Year Instant Download Pdf
Version 1 (Questions 1-100)
SECTION 1: PHARMACOKINETICS & PHARMACODYNAMICS (Questions 1-40)
1. A patient with severe hypoalbuminemia is receiving a highly protein-bound
medication. The nurse anticipates that the free (unbound) drug concentration will be:
A) Decreased, requiring a higher dose
B) Increased, requiring a lower dose
C) Unchanged because binding does not affect free drug levels
D) Decreased because the drug will accumulate in adipose tissue
Answer: B) Increased, requiring a lower dose
Explanation: Hypoalbuminemia reduces available protein binding sites, resulting in a higher
fraction of unbound (free) drug. Free drug is pharmacologically active. Increased free drug
can lead to toxicity, so a lower dose may be needed .
2. A drug that follows zero-order kinetics (e.g., phenytoin at therapeutic doses)
exhibits which characteristic?
,A) A constant fraction of the drug is eliminated per unit time
B) A constant amount of the drug is eliminated per unit time
C) Elimination rate is directly proportional to plasma concentration
D) Half-life remains constant regardless of dose
Answer: B) A constant amount of the drug is eliminated per unit time
Explanation: Zero-order kinetics means the elimination rate is constant regardless of
concentration (e.g., 10 mg/hour). A constant fraction (e.g., 10% per hour) describes first-
order kinetics. Zero-order drugs have a half-life that increases with dose, and small dose
changes can cause large concentration changes .
3. A patient is started on a drug with a half-life of 24 hours. Approximately how many
days will it take to reach steady-state plasma concentrations?
A) 1 day
B) 3 days
C) 5 days
D) 7 days
Answer: C) 5 days
Explanation: Steady state is reached after approximately 4–5 half-lives. With a 24-hour half-
life, steady state occurs in 4–5 days. 7 days would be more than 5 half-lives, but 5 days is
the closest accurate estimate .
,4. Cytochrome P450 (CYP) enzyme induction results in:
A) Decreased metabolism of certain drugs, leading to increased drug levels
B) Increased metabolism of certain drugs, leading to decreased drug levels
C) No change in drug metabolism
D) Decreased renal excretion of drugs
Answer: B) Increased metabolism of certain drugs, leading to decreased drug levels
Explanation: Enzyme induction (e.g., by rifampin, phenytoin, carbamazepine) increases
synthesis or activity of CYP isoenzymes, accelerating metabolism of substrates. This
reduces plasma concentrations and may reduce therapeutic effect .
5. A patient taking warfarin is started on rifampin, a strong CYP2C9 and CYP3A4
inducer. The nurse expects the INR to:
A) Increase, requiring warfarin dose reduction
B) Decrease, requiring warfarin dose increase
C) Remain unchanged
D) Fluctuate unpredictably
Answer: B) Decrease, requiring warfarin dose increase
Explanation: Rifampin induces CYP2C9 (major warfarin metabolizer), increasing warfarin
clearance and lowering INR. The patient will need a higher warfarin dose to maintain
therapeutic INR, and the INR will drop when rifampin is added .
, 6. Grapefruit juice inhibits which cytochrome P450 isoenzyme, leading to increased
levels of certain drugs?
A) CYP2D6
B) CYP3A4
C) CYP1A2
D) CYP2C9
Answer: B) CYP3A4
Explanation: Grapefruit juice irreversibly inhibits intestinal CYP3A4, reducing first-pass
metabolism of substrates (e.g., statins, calcium channel blockers, cyclosporine). This
increases bioavailability and risk of toxicity .
7. A patient has a genetic variant that causes decreased activity of CYP2D6 (poor
metabolizer phenotype). When prescribed codeine, the patient is at risk for:
A) Increased morphine production and toxicity
B) Decreased morphine production and reduced analgesia
C) No change in codeine effect
D) Increased risk of serotonin syndrome
Answer: B) Decreased morphine production and reduced analgesia
Explanation: Codeine is a prodrug that requires O-demethylation via CYP2D6 to form
morphine, the active analgesic. Poor metabolizers produce little morphine, leading to
inadequate pain relief. Ultra-rapid metabolizers are at risk for morphine toxicity .
