NR 565 ADVANCED PHARMACOLOGY FINAL 2026/2027 |
Fundamentals Study Guide | Chamberlain | Pass Guaranteed
- A+ Graded
SECTION 1: Pharmacokinetics & Pharmacodynamics (Q1-Q20)
Q1: A 58-year-old patient taking simvastatin is prescribed clarithromycin for a
respiratory infection. The nurse recognizes this combination increases risk for
myopathy because clarithromycin:
A. Induces CYP3A4, increasing simvastatin metabolism
B. Inhibits CYP3A4, decreasing simvastatin metabolism [CORRECT]
C. Displaces simvastatin from protein binding sites
D. Increases simvastatin renal excretion
Correct Answer: B
Rationale: Clarithromycin is a potent CYP3A4 inhibitor that decreases simvastatin
metabolism, leading to increased statin levels and elevated myopathy/rhabdomyolysis
risk. CYP3A4 induction would decrease levels, protein binding displacement is not the
primary mechanism, and statins are not primarily renally excreted.
Q2: A drug with high first-pass metabolism is administered orally. Compared to IV
administration, the oral bioavailability will be:
A. Significantly higher
B. Significantly lower [CORRECT]
C. Exactly the same
D. Unpredictable
Correct Answer: B
Rationale: High first-pass metabolism means extensive hepatic extraction before the
drug reaches systemic circulation, resulting in significantly lower oral bioavailability
compared to IV administration, which bypasses the portal circulation entirely.
Q3: A patient requires a theophylline loading dose. The desired plasma concentration is
10 mg/L, volume of distribution is 0.6 L/kg, and the patient weighs 80 kg. What loading
dose is required?
,A. 240 mg
B. 480 mg [CORRECT]
C. 960 mg
D. 120 mg
Correct Answer: B
Rationale: Loading dose = Desired concentration × Vd × Weight = 10 mg/L × 0.6 L/kg ×
80 kg = 480 mg. This achieves the target concentration immediately without waiting for
accumulation. The other options represent half, double, or one-quarter of the correct
calculation.
Q4: A patient taking warfarin is started on metronidazole for a bacterial infection. The
nurse should monitor for:
A. Decreased INR and clot formation
B. Increased INR and bleeding risk [CORRECT]
C. Decreased INR and clotting risk
D. No interaction between these agents
Correct Answer: B
Rationale: Metronidazole inhibits CYP2C9 metabolism of warfarin, increasing warfarin
plasma levels and INR, which significantly elevates bleeding risk. The INR would
increase, not decrease, and this is a well-documented major drug-drug interaction.
Q5: Which pharmacodynamic parameter best describes the margin of safety between
the dose that produces therapeutic effects and the dose that produces toxicity?
A. Potency
B. Efficacy
C. Therapeutic index [CORRECT]
D. Bioequivalence
Correct Answer: C
Rationale: The therapeutic index (TI) is the ratio of the toxic dose to the effective dose
(TD50/ED50) and represents the margin of safety. A narrow TI (e.g., digoxin, lithium)
indicates a small difference between therapeutic and toxic doses, requiring close
monitoring.
Q6: A patient on highly protein-bound phenytoin is given aspirin, which also has high
protein binding. The nurse recognizes the most likely immediate effect is:
,A. Increased phenytoin metabolism
B. Transient increase in free phenytoin due to displacement [CORRECT]
C. Decreased phenytoin absorption
D. Increased phenytoin excretion
Correct Answer: B
Rationale: Aspirin can displace phenytoin from albumin binding sites, transiently
increasing free (active) phenytoin levels. Although displacement is usually temporary
due to increased metabolism/excretion of the free drug, it can cause transient toxicity in
susceptible patients.
Q7: A drug is eliminated at a constant rate regardless of plasma concentration. This
describes:
A. First-order kinetics
B. Zero-order kinetics [CORRECT]
C. Michaelis-Menten kinetics
D. Capacity-limited absorption
Correct Answer: B
Rationale: Zero-order kinetics occurs when a fixed amount of drug is eliminated per unit
time regardless of concentration, as seen with phenytoin at high concentrations and
ethanol. First-order kinetics eliminates a constant fraction per unit time, which is more
common at therapeutic doses.
Q8: A drug has a half-life of 6 hours. Approximately how long will it take to reach
steady-state concentration with repeated dosing?
A. 6 hours
B. 12 hours
C. 24 hours
D. 30 hours [CORRECT]
Correct Answer: D
Rationale: Steady state is reached after approximately 5 half-lives (5 × 6 hours = 30
hours). At this point, drug elimination equals drug administration, and plasma
concentrations plateau. One half-life reaches 50% of steady state, not full steady state.
Q9: A patient stabilized on warfarin (INR 2.5) requires amiodarone for atrial fibrillation.
The nurse anticipates the provider will:
, A. Increase the warfarin dose
B. Decrease the warfarin dose and monitor INR closely [CORRECT]
C. Discontinue warfarin and switch to aspirin
D. Maintain the current warfarin dose
Correct Answer: B
Rationale: Amiodarone inhibits CYP2C9 and CYP3A4 metabolism of warfarin, increasing
INR and bleeding risk. The warfarin dose must be decreased (typically by 30-50%) with
frequent INR monitoring until a new stable dose is established.
Q10: A drug that binds to a receptor and produces the same biological response as the
endogenous ligand is classified as:
A. Competitive antagonist
B. Non-competitive antagonist
C. Partial agonist
D. Full agonist [CORRECT]
Correct Answer: D
Rationale: A full agonist binds to a receptor and produces the same maximal biological
response as the endogenous ligand. Antagonists block responses, and partial agonists
produce submaximal responses even at full receptor occupancy.
Q11: An 82-year-old patient has decreased albumin and reduced hepatic blood flow. The
nurse expects which pharmacokinetic change?
A. Increased drug distribution and decreased first-pass metabolism [CORRECT]
B. Decreased drug distribution and increased first-pass metabolism
C. No change in drug pharmacokinetics
D. Increased renal excretion of all drugs
Correct Answer: A
Rationale: In elderly patients, decreased albumin increases free drug fraction (more
distribution), and reduced hepatic blood flow decreases first-pass metabolism,
potentially increasing bioavailability of high-extraction drugs. Renal excretion typically
decreases, not increases, with age.
Q12: The fraction of an administered dose that reaches systemic circulation unchanged
is defined as:
A. Clearance
Fundamentals Study Guide | Chamberlain | Pass Guaranteed
- A+ Graded
SECTION 1: Pharmacokinetics & Pharmacodynamics (Q1-Q20)
Q1: A 58-year-old patient taking simvastatin is prescribed clarithromycin for a
respiratory infection. The nurse recognizes this combination increases risk for
myopathy because clarithromycin:
A. Induces CYP3A4, increasing simvastatin metabolism
B. Inhibits CYP3A4, decreasing simvastatin metabolism [CORRECT]
C. Displaces simvastatin from protein binding sites
D. Increases simvastatin renal excretion
Correct Answer: B
Rationale: Clarithromycin is a potent CYP3A4 inhibitor that decreases simvastatin
metabolism, leading to increased statin levels and elevated myopathy/rhabdomyolysis
risk. CYP3A4 induction would decrease levels, protein binding displacement is not the
primary mechanism, and statins are not primarily renally excreted.
Q2: A drug with high first-pass metabolism is administered orally. Compared to IV
administration, the oral bioavailability will be:
A. Significantly higher
B. Significantly lower [CORRECT]
C. Exactly the same
D. Unpredictable
Correct Answer: B
Rationale: High first-pass metabolism means extensive hepatic extraction before the
drug reaches systemic circulation, resulting in significantly lower oral bioavailability
compared to IV administration, which bypasses the portal circulation entirely.
Q3: A patient requires a theophylline loading dose. The desired plasma concentration is
10 mg/L, volume of distribution is 0.6 L/kg, and the patient weighs 80 kg. What loading
dose is required?
,A. 240 mg
B. 480 mg [CORRECT]
C. 960 mg
D. 120 mg
Correct Answer: B
Rationale: Loading dose = Desired concentration × Vd × Weight = 10 mg/L × 0.6 L/kg ×
80 kg = 480 mg. This achieves the target concentration immediately without waiting for
accumulation. The other options represent half, double, or one-quarter of the correct
calculation.
Q4: A patient taking warfarin is started on metronidazole for a bacterial infection. The
nurse should monitor for:
A. Decreased INR and clot formation
B. Increased INR and bleeding risk [CORRECT]
C. Decreased INR and clotting risk
D. No interaction between these agents
Correct Answer: B
Rationale: Metronidazole inhibits CYP2C9 metabolism of warfarin, increasing warfarin
plasma levels and INR, which significantly elevates bleeding risk. The INR would
increase, not decrease, and this is a well-documented major drug-drug interaction.
Q5: Which pharmacodynamic parameter best describes the margin of safety between
the dose that produces therapeutic effects and the dose that produces toxicity?
A. Potency
B. Efficacy
C. Therapeutic index [CORRECT]
D. Bioequivalence
Correct Answer: C
Rationale: The therapeutic index (TI) is the ratio of the toxic dose to the effective dose
(TD50/ED50) and represents the margin of safety. A narrow TI (e.g., digoxin, lithium)
indicates a small difference between therapeutic and toxic doses, requiring close
monitoring.
Q6: A patient on highly protein-bound phenytoin is given aspirin, which also has high
protein binding. The nurse recognizes the most likely immediate effect is:
,A. Increased phenytoin metabolism
B. Transient increase in free phenytoin due to displacement [CORRECT]
C. Decreased phenytoin absorption
D. Increased phenytoin excretion
Correct Answer: B
Rationale: Aspirin can displace phenytoin from albumin binding sites, transiently
increasing free (active) phenytoin levels. Although displacement is usually temporary
due to increased metabolism/excretion of the free drug, it can cause transient toxicity in
susceptible patients.
Q7: A drug is eliminated at a constant rate regardless of plasma concentration. This
describes:
A. First-order kinetics
B. Zero-order kinetics [CORRECT]
C. Michaelis-Menten kinetics
D. Capacity-limited absorption
Correct Answer: B
Rationale: Zero-order kinetics occurs when a fixed amount of drug is eliminated per unit
time regardless of concentration, as seen with phenytoin at high concentrations and
ethanol. First-order kinetics eliminates a constant fraction per unit time, which is more
common at therapeutic doses.
Q8: A drug has a half-life of 6 hours. Approximately how long will it take to reach
steady-state concentration with repeated dosing?
A. 6 hours
B. 12 hours
C. 24 hours
D. 30 hours [CORRECT]
Correct Answer: D
Rationale: Steady state is reached after approximately 5 half-lives (5 × 6 hours = 30
hours). At this point, drug elimination equals drug administration, and plasma
concentrations plateau. One half-life reaches 50% of steady state, not full steady state.
Q9: A patient stabilized on warfarin (INR 2.5) requires amiodarone for atrial fibrillation.
The nurse anticipates the provider will:
, A. Increase the warfarin dose
B. Decrease the warfarin dose and monitor INR closely [CORRECT]
C. Discontinue warfarin and switch to aspirin
D. Maintain the current warfarin dose
Correct Answer: B
Rationale: Amiodarone inhibits CYP2C9 and CYP3A4 metabolism of warfarin, increasing
INR and bleeding risk. The warfarin dose must be decreased (typically by 30-50%) with
frequent INR monitoring until a new stable dose is established.
Q10: A drug that binds to a receptor and produces the same biological response as the
endogenous ligand is classified as:
A. Competitive antagonist
B. Non-competitive antagonist
C. Partial agonist
D. Full agonist [CORRECT]
Correct Answer: D
Rationale: A full agonist binds to a receptor and produces the same maximal biological
response as the endogenous ligand. Antagonists block responses, and partial agonists
produce submaximal responses even at full receptor occupancy.
Q11: An 82-year-old patient has decreased albumin and reduced hepatic blood flow. The
nurse expects which pharmacokinetic change?
A. Increased drug distribution and decreased first-pass metabolism [CORRECT]
B. Decreased drug distribution and increased first-pass metabolism
C. No change in drug pharmacokinetics
D. Increased renal excretion of all drugs
Correct Answer: A
Rationale: In elderly patients, decreased albumin increases free drug fraction (more
distribution), and reduced hepatic blood flow decreases first-pass metabolism,
potentially increasing bioavailability of high-extraction drugs. Renal excretion typically
decreases, not increases, with age.
Q12: The fraction of an administered dose that reaches systemic circulation unchanged
is defined as:
A. Clearance
