WALDEN UNIVERSITY | NURS 6521: Advanced Pharmacology Midterm Exam - Set 3 - Spring 2026/2027
NURS 6521: Advanced Pharmacology — Midterm
Examination
Walden University — College of Nursing — Spring 2026/2027 (Set 3)
Graduate-Level Advanced Practice Nursing Prescriber Examination — Complete Answers with Detailed
Rationales
EXAMINATION INSTRUCTIONS
Format: 100 multiple-choice questions, four options (A–D), ONE best answer per item. Each question is followed by the correct
answer and a detailed prescriber-level rationale.
Cognitive distribution: ~25% recall (pharmacology mechanisms and classifications), ~55% application (prescriber scenarios
requiring drug selection, dosing, and monitoring), ~20% analysis (drug interaction identification, polypharmacy deprescribing,
pharmacogenomic decision-making).
Content scope: Pharmacokinetics & pharmacodynamics; pharmacogenomics & individual variation; drug interactions, adverse
effects & toxicity; cardiovascular, respiratory, endocrine, anti-infective, CNS, and GI/renal/musculoskeletal pharmacology.
Reflects 2026/2027 FDA approvals, revised prescribing guidelines, and current Black Box Warnings.
Prescriber focus: Many items require selection of the MOST appropriate medication based on patient-specific factors (age,
weight, renal/hepatic function, comorbidities, concurrent therapies, genetic polymorphisms). Distractors represent common
advanced pharmacology exam pitfalls including contraindicated agents, missed interactions, incorrect renal/hepatic dosing,
misidentified Black Box warnings, and incorrect monitoring parameters.
Use: This examination is intended for self-assessment and board-style preparation. The provided rationales explain both why the
correct option is best AND why each distractor is suboptimal or contraindicated, integrating pharmacokinetic principles,
pharmacodynamic mechanisms, evidence-based prescribing guidelines, and patient-specific monitoring requirements.
SECTION 1: Pharmacokinetics and Pharmacodynamics (Absorption, Distribution,
Metabolism, Excretion, & Receptor Theory)
Items 1–15. Covers bioavailability, first-pass effect, volume of distribution, half-life and steady state, receptor theory
(agonists, partial agonists, antagonists), dose-response relationships, and therapeutic index.
1. A 54-year-old female with newly diagnosed generalized tonic-clonic seizures is started on an oral antiepileptic
medication. The prescriber notes that the oral formulation produces a peak plasma concentration roughly
one-third of that achieved with the same dose given intravenously. Which pharmacokinetic property best
explains this observation?
A. High volume of distribution
B. Low plasma protein binding
C. Low systemic bioavailability due to first-pass hepatic metabolism [CORRECT]
D. Rapid renal tubular reabsorption
Correct Answer: C — Low systemic bioavailability due to first-pass hepatic metabolism
Rationale: Bioavailability is the fraction of administered dose that reaches systemic circulation unchanged. Oral drugs
absorbed via the portal circulation must first pass through the liver, where a portion is metabolized before reaching systemic
blood (first-pass effect), producing a lower peak than the IV dose. Volume of distribution affects concentration at steady state
but not the oral/IV ratio, protein binding affects free fraction rather than absolute bioavailability, and renal tubular
reabsorption influences elimination half-life rather than peak concentration after oral dosing.
NURS 6521 - Pharmacology Midterm - Set 3 - Complete Answers Page 1
,WALDEN UNIVERSITY | NURS 6521: Advanced Pharmacology Midterm Exam - Set 3 - Spring 2026/2027
2. A patient receiving oral phenytoin for partial seizures has a calculated volume of distribution (Vd) of 0.65
L/kg. Which clinical interpretation is most accurate regarding this Vd value?
A. The drug is confined predominantly to the intravascular space
B. The drug distributes extensively into total body water and likely binds tissue proteins [CORRECT]
C. The drug is highly ionized at physiologic pH and cannot cross cell membranes
D. The drug has zero hepatic extraction ratio
Correct Answer: B — The drug distributes extensively into total body water and likely binds tissue
proteins
Rationale: Phenytoin has a Vd of approximately 0.6-0.8 L/kg, indicating distribution into total body water with significant
tissue protein binding. Drugs confined to plasma have a Vd of roughly 0.05 L/kg (e.g., albumin), and Vd values near 0.6-0.7
L/kg indicate penetration well beyond plasma into extracellular and intracellular compartments. Vd does not directly indicate
ionization state or hepatic extraction ratio; those are independent properties. The large Vd also explains why phenytoin
requires a loading dose for rapid therapeutic levels.
3. A patient is started on a maintenance dose of digoxin 0.25 mg PO daily. Digoxin has a half-life of
approximately 36 hours. Approximately how long will it take to reach steady-state serum concentrations
assuming no loading dose is given?
A. 12 hours
B. 36 hours
C. 3 days
D. 7-9 days (roughly 4-5 half-lives) [CORRECT]
Correct Answer: D — 7-9 days (roughly 4-5 half-lives)
Rationale: Steady state is reached after approximately 4-5 half-lives of repeated dosing. With a t1/2 of 36 hours, 4-5
half-lives equals 144-180 hours (6-7.5 days), so 7-9 days is the clinically appropriate estimate. At 36 hours only one half-life
has elapsed (50% of steady state), and 3 days (72 hours, two half-lives) achieves only 75% of steady state. This principle
justifies loading doses for drugs needing rapid effect (digoxin, amiodarone, phenytoin) when waiting 4-5 half-lives is
clinically unacceptable.
4. A clinical trial compares a full mu-opioid agonist (morphine), a partial agonist (buprenorphine), and a
competitive antagonist (naloxone) at the mu receptor. Which statement best characterizes the
pharmacodynamic difference between a partial agonist and a full agonist at the same receptor?
A. A partial agonist has lower receptor affinity but higher efficacy than a full agonist
B. A partial agonist has lower intrinsic efficacy even at full receptor occupancy, producing a submaximal
response [CORRECT]
C. A partial agonist cannot bind the receptor in the presence of an antagonist
D. A partial agonist only acts at receptors located in the central nervous system
Correct Answer: B — A partial agonist has lower intrinsic efficacy even at full receptor occupancy,
producing a submaximal response
Rationale: Efficacy (intrinsic activity) and affinity are independent properties. A partial agonist binds the receptor with
comparable affinity but produces a submaximal response even at full receptor occupancy, because its intrinsic efficacy is
lower than a full agonist. This is why buprenorphine produces a ceiling respiratory depression and can displace full agonists
(precipitating withdrawal). Affinity differences, receptor localization, and antagonist interference are not what defines partial
agonism; the defining feature is reduced maximal effect (Emax) at full occupancy.
NURS 6521 - Pharmacology Midterm - Set 3 - Complete Answers Page 2
,WALDEN UNIVERSITY | NURS 6521: Advanced Pharmacology Midterm Exam - Set 3 - Spring 2026/2027
5. A 47-year-old patient on long-acting morphine for chronic cancer pain is given IV naloxone for
opioid-induced respiratory depression. Within minutes the patient becomes tachypneic and reports severe pain.
Which pharmacodynamic mechanism best explains this reversal?
A. Naloxone upregulates mu receptors, increasing endogenous opioid activity
B. Naloxone acts as a competitive antagonist at the mu receptor, displacing morphine and reducing receptor
occupancy [CORRECT]
C. Naloxone accelerates hepatic metabolism of morphine via CYP3A4 induction
D. Naloxone forms an inactive covalent complex with morphine in plasma
Correct Answer: B — Naloxone acts as a competitive antagonist at the mu receptor, displacing
morphine and reducing receptor occupancy
Rationale: Naloxone is a high-affinity competitive antagonist at mu, kappa, and delta receptors; it binds the same site as
morphine but produces no intrinsic activity, effectively displacing morphine and reversing both respiratory depression and
analgesia. The reversal is pharmacodynamic, not pharmacokinetic; naloxone does not accelerate morphine metabolism or
chemically neutralize it. Because naloxone has a shorter half-life (30-90 min) than many opioids, repeated dosing or infusion
may be required to prevent recurrent respiratory depression.
6. A patient with stage 1 hypertension has a baseline blood pressure of 152/96 mmHg. After the first dose of an
antihypertensive, the BP falls to 144/90 mmHg; doubling the dose reduces it to 138/86; quadrupling reduces it
to 134/84; an eightfold increase only achieves 132/84. This pattern is best described by which pharmacodynamic
concept?
A. Steep dose-response curve
B. Quantal dose-response relationship
C. Graded dose-response curve that plateaus at Emax [CORRECT]
D. Inverse agonism
Correct Answer: C — Graded dose-response curve that plateaus at Emax
Rationale: A graded dose-response curve plots the magnitude of an individual patient response against increasing dose. The
response increases proportionally at low doses, then plateaus near Emax (maximal effect the drug can produce) despite further
dose escalation. The flattening response (152 to 144 to 138 to 134 to 132) demonstrates approaching Emax. A quantal
response is all-or-none in a population (e.g., % of patients who respond), not a graded individual response. Steep slope and
inverse agonism describe other curve properties not illustrated here.
7. Lithium has a narrow therapeutic index with a therapeutic serum range of 0.6-1.2 mEq/L; toxicity appears
above 1.5 mEq/L. Which clinical consideration is most appropriate given this property?
A. Lithium doses can be safely doubled if a single level is subtherapeutic
B. Routine serum drug monitoring and patient education on signs of toxicity are mandatory [CORRECT]
C. Lithium has a flat dose-response curve and toxic doses rarely cause harm
D. Lithium can be prescribed without renal function monitoring because it is hepatically metabolized
Correct Answer: B — Routine serum drug monitoring and patient education on signs of toxicity are
mandatory
Rationale: A narrow therapeutic index means the toxic dose is close to the therapeutic dose, mandating serum concentration
monitoring, dose individualization, and patient education on early toxicity (tremor, GI upset, confusion, polyuria). Lithium is
excreted unchanged by the kidney and requires renal function monitoring; it is NOT hepatically metabolized. Doubling doses
blindly is dangerous because lithium toxicity (especially above 2.0 mEq/L) can cause seizures, arrhythmias, and renal failure.
The dose-response is steep, not flat.
NURS 6521 - Pharmacology Midterm - Set 3 - Complete Answers Page 3
, WALDEN UNIVERSITY | NURS 6521: Advanced Pharmacology Midterm Exam - Set 3 - Spring 2026/2027
8. A drug with high first-pass metabolism is being considered for a patient with severe hepatic cirrhosis and
portal hypertension. The prescriber must choose between oral and sublingual routes. Which pharmacokinetic
rationale supports sublingual administration in this patient?
A. Sublingual absorption bypasses the portal circulation and hepatic first-pass metabolism [CORRECT]
B. Sublingual absorption is slower and produces less peak-related adverse effects
C. Sublingual absorption requires gastric acid for activation
D. Sublingual absorption is increased by hepatic enzyme induction
Correct Answer: A — Sublingual absorption bypasses the portal circulation and hepatic first-pass
metabolism
Rationale: Sublingual administration allows drug absorption directly into the systemic venous circulation via the oral
mucosa, bypassing the portal vein and the liver first-pass metabolism that significantly reduces oral bioavailability of drugs
such as nitroglycerin, propranolol, and certain opioids. In cirrhosis with impaired hepatic metabolism, the difference is even
more pronounced because hepatic clearance is further reduced. Sublingual absorption is generally faster (not slower), does not
require gastric acid, and is independent of hepatic enzyme induction.
9. A new drug in development shows 95% plasma protein binding, primarily to albumin. In a patient with
severe hypoalbuminemia (albumin 1.8 g/dL), which pharmacokinetic change is most likely?
A. Decreased free (active) drug concentration leading to therapeutic failure
B. Increased free (active) drug concentration and risk of toxicity, with shortened half-life [CORRECT]
C. No change in free drug because albumin does not bind acidic drugs
D. Increased Vd because the drug shifts entirely into red blood cells
Correct Answer: B — Increased free (active) drug concentration and risk of toxicity, with shortened
half-life
Rationale: With severe hypoalbuminemia, fewer albumin binding sites are available, increasing the free (unbound) fraction
of highly albumin-bound drugs. The free fraction is what produces pharmacologic effect and what is cleared by liver and
kidney, so toxicity risk rises while half-life may shorten (more free drug cleared). The total (bound + free) concentration may
appear low, but the active free fraction is elevated. Albumin does bind acidic drugs (alpha-1-acid glycoprotein binds basic
drugs), so option C is incorrect.
10. A 68-year-old male with chronic kidney disease (eGFR 22 mL/min/1.73 m²) is started on a renally cleared
medication with a therapeutic half-life of 8 hours in normal renal function. Which pharmacokinetic change is
most expected, and what is the most appropriate prescriber response?
A. Half-life remains 8 hours; no dose adjustment needed
B. Half-life is shortened; increase the dose to maintain effect
C. Half-life is prolonged; extend dosing interval or reduce dose [CORRECT]
D. Half-life is prolonged; add a loading dose to compensate
Correct Answer: C — Half-life is prolonged; extend dosing interval or reduce dose
Rationale: Renally cleared drugs accumulate when GFR falls, prolonging half-life and increasing toxicity risk. The
appropriate response is to extend the dosing interval (e.g., from q12h to q24h) or reduce individual doses, or both. Adding a
loading dose does not address accumulation and may worsen toxicity. Increasing dose would further elevate steady-state
concentrations. Examples include gabapentin, pregabalin, allopurinol, apixaban, and many antibiotics, all of which require
renal dose adjustment based on CrCl or eGFR.
NURS 6521 - Pharmacology Midterm - Set 3 - Complete Answers Page 4
NURS 6521: Advanced Pharmacology — Midterm
Examination
Walden University — College of Nursing — Spring 2026/2027 (Set 3)
Graduate-Level Advanced Practice Nursing Prescriber Examination — Complete Answers with Detailed
Rationales
EXAMINATION INSTRUCTIONS
Format: 100 multiple-choice questions, four options (A–D), ONE best answer per item. Each question is followed by the correct
answer and a detailed prescriber-level rationale.
Cognitive distribution: ~25% recall (pharmacology mechanisms and classifications), ~55% application (prescriber scenarios
requiring drug selection, dosing, and monitoring), ~20% analysis (drug interaction identification, polypharmacy deprescribing,
pharmacogenomic decision-making).
Content scope: Pharmacokinetics & pharmacodynamics; pharmacogenomics & individual variation; drug interactions, adverse
effects & toxicity; cardiovascular, respiratory, endocrine, anti-infective, CNS, and GI/renal/musculoskeletal pharmacology.
Reflects 2026/2027 FDA approvals, revised prescribing guidelines, and current Black Box Warnings.
Prescriber focus: Many items require selection of the MOST appropriate medication based on patient-specific factors (age,
weight, renal/hepatic function, comorbidities, concurrent therapies, genetic polymorphisms). Distractors represent common
advanced pharmacology exam pitfalls including contraindicated agents, missed interactions, incorrect renal/hepatic dosing,
misidentified Black Box warnings, and incorrect monitoring parameters.
Use: This examination is intended for self-assessment and board-style preparation. The provided rationales explain both why the
correct option is best AND why each distractor is suboptimal or contraindicated, integrating pharmacokinetic principles,
pharmacodynamic mechanisms, evidence-based prescribing guidelines, and patient-specific monitoring requirements.
SECTION 1: Pharmacokinetics and Pharmacodynamics (Absorption, Distribution,
Metabolism, Excretion, & Receptor Theory)
Items 1–15. Covers bioavailability, first-pass effect, volume of distribution, half-life and steady state, receptor theory
(agonists, partial agonists, antagonists), dose-response relationships, and therapeutic index.
1. A 54-year-old female with newly diagnosed generalized tonic-clonic seizures is started on an oral antiepileptic
medication. The prescriber notes that the oral formulation produces a peak plasma concentration roughly
one-third of that achieved with the same dose given intravenously. Which pharmacokinetic property best
explains this observation?
A. High volume of distribution
B. Low plasma protein binding
C. Low systemic bioavailability due to first-pass hepatic metabolism [CORRECT]
D. Rapid renal tubular reabsorption
Correct Answer: C — Low systemic bioavailability due to first-pass hepatic metabolism
Rationale: Bioavailability is the fraction of administered dose that reaches systemic circulation unchanged. Oral drugs
absorbed via the portal circulation must first pass through the liver, where a portion is metabolized before reaching systemic
blood (first-pass effect), producing a lower peak than the IV dose. Volume of distribution affects concentration at steady state
but not the oral/IV ratio, protein binding affects free fraction rather than absolute bioavailability, and renal tubular
reabsorption influences elimination half-life rather than peak concentration after oral dosing.
NURS 6521 - Pharmacology Midterm - Set 3 - Complete Answers Page 1
,WALDEN UNIVERSITY | NURS 6521: Advanced Pharmacology Midterm Exam - Set 3 - Spring 2026/2027
2. A patient receiving oral phenytoin for partial seizures has a calculated volume of distribution (Vd) of 0.65
L/kg. Which clinical interpretation is most accurate regarding this Vd value?
A. The drug is confined predominantly to the intravascular space
B. The drug distributes extensively into total body water and likely binds tissue proteins [CORRECT]
C. The drug is highly ionized at physiologic pH and cannot cross cell membranes
D. The drug has zero hepatic extraction ratio
Correct Answer: B — The drug distributes extensively into total body water and likely binds tissue
proteins
Rationale: Phenytoin has a Vd of approximately 0.6-0.8 L/kg, indicating distribution into total body water with significant
tissue protein binding. Drugs confined to plasma have a Vd of roughly 0.05 L/kg (e.g., albumin), and Vd values near 0.6-0.7
L/kg indicate penetration well beyond plasma into extracellular and intracellular compartments. Vd does not directly indicate
ionization state or hepatic extraction ratio; those are independent properties. The large Vd also explains why phenytoin
requires a loading dose for rapid therapeutic levels.
3. A patient is started on a maintenance dose of digoxin 0.25 mg PO daily. Digoxin has a half-life of
approximately 36 hours. Approximately how long will it take to reach steady-state serum concentrations
assuming no loading dose is given?
A. 12 hours
B. 36 hours
C. 3 days
D. 7-9 days (roughly 4-5 half-lives) [CORRECT]
Correct Answer: D — 7-9 days (roughly 4-5 half-lives)
Rationale: Steady state is reached after approximately 4-5 half-lives of repeated dosing. With a t1/2 of 36 hours, 4-5
half-lives equals 144-180 hours (6-7.5 days), so 7-9 days is the clinically appropriate estimate. At 36 hours only one half-life
has elapsed (50% of steady state), and 3 days (72 hours, two half-lives) achieves only 75% of steady state. This principle
justifies loading doses for drugs needing rapid effect (digoxin, amiodarone, phenytoin) when waiting 4-5 half-lives is
clinically unacceptable.
4. A clinical trial compares a full mu-opioid agonist (morphine), a partial agonist (buprenorphine), and a
competitive antagonist (naloxone) at the mu receptor. Which statement best characterizes the
pharmacodynamic difference between a partial agonist and a full agonist at the same receptor?
A. A partial agonist has lower receptor affinity but higher efficacy than a full agonist
B. A partial agonist has lower intrinsic efficacy even at full receptor occupancy, producing a submaximal
response [CORRECT]
C. A partial agonist cannot bind the receptor in the presence of an antagonist
D. A partial agonist only acts at receptors located in the central nervous system
Correct Answer: B — A partial agonist has lower intrinsic efficacy even at full receptor occupancy,
producing a submaximal response
Rationale: Efficacy (intrinsic activity) and affinity are independent properties. A partial agonist binds the receptor with
comparable affinity but produces a submaximal response even at full receptor occupancy, because its intrinsic efficacy is
lower than a full agonist. This is why buprenorphine produces a ceiling respiratory depression and can displace full agonists
(precipitating withdrawal). Affinity differences, receptor localization, and antagonist interference are not what defines partial
agonism; the defining feature is reduced maximal effect (Emax) at full occupancy.
NURS 6521 - Pharmacology Midterm - Set 3 - Complete Answers Page 2
,WALDEN UNIVERSITY | NURS 6521: Advanced Pharmacology Midterm Exam - Set 3 - Spring 2026/2027
5. A 47-year-old patient on long-acting morphine for chronic cancer pain is given IV naloxone for
opioid-induced respiratory depression. Within minutes the patient becomes tachypneic and reports severe pain.
Which pharmacodynamic mechanism best explains this reversal?
A. Naloxone upregulates mu receptors, increasing endogenous opioid activity
B. Naloxone acts as a competitive antagonist at the mu receptor, displacing morphine and reducing receptor
occupancy [CORRECT]
C. Naloxone accelerates hepatic metabolism of morphine via CYP3A4 induction
D. Naloxone forms an inactive covalent complex with morphine in plasma
Correct Answer: B — Naloxone acts as a competitive antagonist at the mu receptor, displacing
morphine and reducing receptor occupancy
Rationale: Naloxone is a high-affinity competitive antagonist at mu, kappa, and delta receptors; it binds the same site as
morphine but produces no intrinsic activity, effectively displacing morphine and reversing both respiratory depression and
analgesia. The reversal is pharmacodynamic, not pharmacokinetic; naloxone does not accelerate morphine metabolism or
chemically neutralize it. Because naloxone has a shorter half-life (30-90 min) than many opioids, repeated dosing or infusion
may be required to prevent recurrent respiratory depression.
6. A patient with stage 1 hypertension has a baseline blood pressure of 152/96 mmHg. After the first dose of an
antihypertensive, the BP falls to 144/90 mmHg; doubling the dose reduces it to 138/86; quadrupling reduces it
to 134/84; an eightfold increase only achieves 132/84. This pattern is best described by which pharmacodynamic
concept?
A. Steep dose-response curve
B. Quantal dose-response relationship
C. Graded dose-response curve that plateaus at Emax [CORRECT]
D. Inverse agonism
Correct Answer: C — Graded dose-response curve that plateaus at Emax
Rationale: A graded dose-response curve plots the magnitude of an individual patient response against increasing dose. The
response increases proportionally at low doses, then plateaus near Emax (maximal effect the drug can produce) despite further
dose escalation. The flattening response (152 to 144 to 138 to 134 to 132) demonstrates approaching Emax. A quantal
response is all-or-none in a population (e.g., % of patients who respond), not a graded individual response. Steep slope and
inverse agonism describe other curve properties not illustrated here.
7. Lithium has a narrow therapeutic index with a therapeutic serum range of 0.6-1.2 mEq/L; toxicity appears
above 1.5 mEq/L. Which clinical consideration is most appropriate given this property?
A. Lithium doses can be safely doubled if a single level is subtherapeutic
B. Routine serum drug monitoring and patient education on signs of toxicity are mandatory [CORRECT]
C. Lithium has a flat dose-response curve and toxic doses rarely cause harm
D. Lithium can be prescribed without renal function monitoring because it is hepatically metabolized
Correct Answer: B — Routine serum drug monitoring and patient education on signs of toxicity are
mandatory
Rationale: A narrow therapeutic index means the toxic dose is close to the therapeutic dose, mandating serum concentration
monitoring, dose individualization, and patient education on early toxicity (tremor, GI upset, confusion, polyuria). Lithium is
excreted unchanged by the kidney and requires renal function monitoring; it is NOT hepatically metabolized. Doubling doses
blindly is dangerous because lithium toxicity (especially above 2.0 mEq/L) can cause seizures, arrhythmias, and renal failure.
The dose-response is steep, not flat.
NURS 6521 - Pharmacology Midterm - Set 3 - Complete Answers Page 3
, WALDEN UNIVERSITY | NURS 6521: Advanced Pharmacology Midterm Exam - Set 3 - Spring 2026/2027
8. A drug with high first-pass metabolism is being considered for a patient with severe hepatic cirrhosis and
portal hypertension. The prescriber must choose between oral and sublingual routes. Which pharmacokinetic
rationale supports sublingual administration in this patient?
A. Sublingual absorption bypasses the portal circulation and hepatic first-pass metabolism [CORRECT]
B. Sublingual absorption is slower and produces less peak-related adverse effects
C. Sublingual absorption requires gastric acid for activation
D. Sublingual absorption is increased by hepatic enzyme induction
Correct Answer: A — Sublingual absorption bypasses the portal circulation and hepatic first-pass
metabolism
Rationale: Sublingual administration allows drug absorption directly into the systemic venous circulation via the oral
mucosa, bypassing the portal vein and the liver first-pass metabolism that significantly reduces oral bioavailability of drugs
such as nitroglycerin, propranolol, and certain opioids. In cirrhosis with impaired hepatic metabolism, the difference is even
more pronounced because hepatic clearance is further reduced. Sublingual absorption is generally faster (not slower), does not
require gastric acid, and is independent of hepatic enzyme induction.
9. A new drug in development shows 95% plasma protein binding, primarily to albumin. In a patient with
severe hypoalbuminemia (albumin 1.8 g/dL), which pharmacokinetic change is most likely?
A. Decreased free (active) drug concentration leading to therapeutic failure
B. Increased free (active) drug concentration and risk of toxicity, with shortened half-life [CORRECT]
C. No change in free drug because albumin does not bind acidic drugs
D. Increased Vd because the drug shifts entirely into red blood cells
Correct Answer: B — Increased free (active) drug concentration and risk of toxicity, with shortened
half-life
Rationale: With severe hypoalbuminemia, fewer albumin binding sites are available, increasing the free (unbound) fraction
of highly albumin-bound drugs. The free fraction is what produces pharmacologic effect and what is cleared by liver and
kidney, so toxicity risk rises while half-life may shorten (more free drug cleared). The total (bound + free) concentration may
appear low, but the active free fraction is elevated. Albumin does bind acidic drugs (alpha-1-acid glycoprotein binds basic
drugs), so option C is incorrect.
10. A 68-year-old male with chronic kidney disease (eGFR 22 mL/min/1.73 m²) is started on a renally cleared
medication with a therapeutic half-life of 8 hours in normal renal function. Which pharmacokinetic change is
most expected, and what is the most appropriate prescriber response?
A. Half-life remains 8 hours; no dose adjustment needed
B. Half-life is shortened; increase the dose to maintain effect
C. Half-life is prolonged; extend dosing interval or reduce dose [CORRECT]
D. Half-life is prolonged; add a loading dose to compensate
Correct Answer: C — Half-life is prolonged; extend dosing interval or reduce dose
Rationale: Renally cleared drugs accumulate when GFR falls, prolonging half-life and increasing toxicity risk. The
appropriate response is to extend the dosing interval (e.g., from q12h to q24h) or reduce individual doses, or both. Adding a
loading dose does not address accumulation and may worsen toxicity. Increasing dose would further elevate steady-state
concentrations. Examples include gabapentin, pregabalin, allopurinol, apixaban, and many antibiotics, all of which require
renal dose adjustment based on CrCl or eGFR.
NURS 6521 - Pharmacology Midterm - Set 3 - Complete Answers Page 4
