NR565 ADVANCED PHARMACOLOGY CARE OF THE
FUNDAMENTALS MIDTERM EXAM 2026/2027 | Questions and
Verified Answers | Chamberlain College | Pass Guaranteed -
A+ Graded
Unit 1: Pharmacokinetics & Pharmacodynamics (15 Questions)
Q1: A 68-year-old male with heart failure is prescribed digoxin 0.25 mg daily. His serum
creatinine is 1.8 mg/dL (eGFR 35 mL/min). The prescriber reduces the dose to 0.125
mg daily. Which pharmacokinetic principle explains this dose adjustment?
A. Increased absorption in the GI tract due to reduced cardiac output
B. Decreased renal elimination requiring dose reduction to prevent toxicity [CORRECT]
C. Increased hepatic metabolism in elderly patients
D. Enhanced receptor sensitivity in heart failure patients
Correct Answer: B
Rationale: Digoxin is primarily eliminated unchanged by the kidneys (60-80%). In
patients with reduced renal function (eGFR <60 mL/min), the elimination half-life is
prolonged from the normal 36-48 hours to 3-5 days or longer. Without dose adjustment,
digoxin accumulates, leading to toxicity (nausea, arrhythmias, visual disturbances). The
loading dose may remain the same, but the maintenance dose must be reduced
proportionally to creatinine clearance or eGFR. Monitoring of serum digoxin levels
(therapeutic 0.5-0.9 ng/mL for heart failure) and renal function is essential.
,Option A is incorrect because digoxin absorption is not significantly altered by cardiac
output; bioavailability is approximately 70-80% and depends on formulation. Option C is
incorrect because digoxin is not significantly metabolized by the liver; renal elimination
is the primary concern. Option D is incorrect because while digoxin has narrow
therapeutic index, receptor sensitivity is not the primary reason for dose adjustment in
renal impairment—accumulation from reduced clearance is the critical factor.
Q2: A patient taking warfarin for atrial fibrillation has an INR of 4.5 (therapeutic range
2.0-3.0) after starting a course of ciprofloxacin for urinary tract infection. Which
pharmacokinetic mechanism explains this interaction?
A. Ciprofloxacin inhibits CYP2C9, reducing warfarin metabolism [CORRECT]
B. Ciprofloxacin induces CYP3A4, increasing warfarin clearance
C. Ciprofloxacin displaces warfarin from plasma albumin binding sites
D. Ciprofloxacin enhances renal excretion of warfarin
Correct Answer: A
Rationale: Warfarin is a racemic mixture; S-warfarin (more potent) is metabolized
primarily by CYP2C9, while R-warfarin is metabolized by CYP1A2 and CYP3A4.
Ciprofloxacin is a moderate inhibitor of CYP1A2 and can also inhibit CYP3A4, affecting
R-warfarin metabolism. More importantly, fluoroquinolones can inhibit CYP2C9 to some
degree and also disrupt vitamin K-producing gut flora, further enhancing warfarin's
effect. This results in decreased warfarin clearance, increased plasma concentration,
and elevated INR with increased bleeding risk. Alternative antibiotics (amoxicillin,
nitrofurantoin) are preferred in patients on warfarin.
,Option B is incorrect because ciprofloxacin inhibits rather than induces cytochrome
P450 enzymes. Option C is incorrect because while warfarin is highly protein-bound
(99%), displacement interactions are transient and less clinically significant than
metabolic inhibition. Option D is incorrect because warfarin is not renally excreted; it is
hepatically metabolized.
Q3: [SATA] Which factors can increase the absorption of an orally administered
medication? (Select all that apply)
A. Increased gastric emptying time
B. Administration with food that enhances solubility
C. Increased blood flow to the gastrointestinal tract
D. High first-pass metabolism in the liver
E. Presence of food that increases bile secretion [CORRECT: B, C, E]
Correct Answer: B, C, E
Rationale:
B is correct: Food can enhance absorption of lipophilic drugs by stimulating bile
secretion, which aids in solubilization and micelle formation. Examples include
griseofulvin and itraconazole, which should be taken with fatty meals.
C is correct: Increased splanchnic blood flow (postprandial state) maintains the
concentration gradient between gut lumen and plasma, enhancing absorption according
to Fick's law of diffusion.
, E is correct: Bile secretion emulsifies fats and fat-soluble drugs, increasing their surface
area for absorption. This is particularly important for vitamins A, D, E, K and lipophilic
medications.
A is incorrect: Increased gastric emptying time (gastric stasis) generally delays
absorption by slowing delivery to the small intestine, where most absorption occurs.
However, for acid-labile drugs, delayed gastric emptying might paradoxically increase
degradation.
D is incorrect: High first-pass metabolism decreases systemic bioavailability by
extracting drug during initial passage through the liver, regardless of absorption
efficiency. This is a post-absorption factor affecting availability, not absorption itself.
Q4: A patient with severe liver cirrhosis is prescribed lorazepam instead of diazepam for
anxiety. Which pharmacokinetic rationale supports this selection?
A. Lorazepam undergoes glucuronidation, which is preserved in liver disease, while
diazepam requires oxidation [CORRECT]
B. Lorazepam has higher oral bioavailability than diazepam
C. Lorazepam is renally eliminated and unaffected by liver function
D. Lorazepam has a larger volume of distribution in cirrhosis
Correct Answer: A
Rationale: In severe liver disease (cirrhosis, hepatitis), Phase I reactions (oxidation,
reduction, hydrolysis via CYP450 enzymes) are significantly impaired due to hepatocyte
damage and reduced enzyme content. Phase II reactions (glucuronidation, sulfation,
acetylation) are relatively preserved until very advanced disease. Diazepam undergoes
FUNDAMENTALS MIDTERM EXAM 2026/2027 | Questions and
Verified Answers | Chamberlain College | Pass Guaranteed -
A+ Graded
Unit 1: Pharmacokinetics & Pharmacodynamics (15 Questions)
Q1: A 68-year-old male with heart failure is prescribed digoxin 0.25 mg daily. His serum
creatinine is 1.8 mg/dL (eGFR 35 mL/min). The prescriber reduces the dose to 0.125
mg daily. Which pharmacokinetic principle explains this dose adjustment?
A. Increased absorption in the GI tract due to reduced cardiac output
B. Decreased renal elimination requiring dose reduction to prevent toxicity [CORRECT]
C. Increased hepatic metabolism in elderly patients
D. Enhanced receptor sensitivity in heart failure patients
Correct Answer: B
Rationale: Digoxin is primarily eliminated unchanged by the kidneys (60-80%). In
patients with reduced renal function (eGFR <60 mL/min), the elimination half-life is
prolonged from the normal 36-48 hours to 3-5 days or longer. Without dose adjustment,
digoxin accumulates, leading to toxicity (nausea, arrhythmias, visual disturbances). The
loading dose may remain the same, but the maintenance dose must be reduced
proportionally to creatinine clearance or eGFR. Monitoring of serum digoxin levels
(therapeutic 0.5-0.9 ng/mL for heart failure) and renal function is essential.
,Option A is incorrect because digoxin absorption is not significantly altered by cardiac
output; bioavailability is approximately 70-80% and depends on formulation. Option C is
incorrect because digoxin is not significantly metabolized by the liver; renal elimination
is the primary concern. Option D is incorrect because while digoxin has narrow
therapeutic index, receptor sensitivity is not the primary reason for dose adjustment in
renal impairment—accumulation from reduced clearance is the critical factor.
Q2: A patient taking warfarin for atrial fibrillation has an INR of 4.5 (therapeutic range
2.0-3.0) after starting a course of ciprofloxacin for urinary tract infection. Which
pharmacokinetic mechanism explains this interaction?
A. Ciprofloxacin inhibits CYP2C9, reducing warfarin metabolism [CORRECT]
B. Ciprofloxacin induces CYP3A4, increasing warfarin clearance
C. Ciprofloxacin displaces warfarin from plasma albumin binding sites
D. Ciprofloxacin enhances renal excretion of warfarin
Correct Answer: A
Rationale: Warfarin is a racemic mixture; S-warfarin (more potent) is metabolized
primarily by CYP2C9, while R-warfarin is metabolized by CYP1A2 and CYP3A4.
Ciprofloxacin is a moderate inhibitor of CYP1A2 and can also inhibit CYP3A4, affecting
R-warfarin metabolism. More importantly, fluoroquinolones can inhibit CYP2C9 to some
degree and also disrupt vitamin K-producing gut flora, further enhancing warfarin's
effect. This results in decreased warfarin clearance, increased plasma concentration,
and elevated INR with increased bleeding risk. Alternative antibiotics (amoxicillin,
nitrofurantoin) are preferred in patients on warfarin.
,Option B is incorrect because ciprofloxacin inhibits rather than induces cytochrome
P450 enzymes. Option C is incorrect because while warfarin is highly protein-bound
(99%), displacement interactions are transient and less clinically significant than
metabolic inhibition. Option D is incorrect because warfarin is not renally excreted; it is
hepatically metabolized.
Q3: [SATA] Which factors can increase the absorption of an orally administered
medication? (Select all that apply)
A. Increased gastric emptying time
B. Administration with food that enhances solubility
C. Increased blood flow to the gastrointestinal tract
D. High first-pass metabolism in the liver
E. Presence of food that increases bile secretion [CORRECT: B, C, E]
Correct Answer: B, C, E
Rationale:
B is correct: Food can enhance absorption of lipophilic drugs by stimulating bile
secretion, which aids in solubilization and micelle formation. Examples include
griseofulvin and itraconazole, which should be taken with fatty meals.
C is correct: Increased splanchnic blood flow (postprandial state) maintains the
concentration gradient between gut lumen and plasma, enhancing absorption according
to Fick's law of diffusion.
, E is correct: Bile secretion emulsifies fats and fat-soluble drugs, increasing their surface
area for absorption. This is particularly important for vitamins A, D, E, K and lipophilic
medications.
A is incorrect: Increased gastric emptying time (gastric stasis) generally delays
absorption by slowing delivery to the small intestine, where most absorption occurs.
However, for acid-labile drugs, delayed gastric emptying might paradoxically increase
degradation.
D is incorrect: High first-pass metabolism decreases systemic bioavailability by
extracting drug during initial passage through the liver, regardless of absorption
efficiency. This is a post-absorption factor affecting availability, not absorption itself.
Q4: A patient with severe liver cirrhosis is prescribed lorazepam instead of diazepam for
anxiety. Which pharmacokinetic rationale supports this selection?
A. Lorazepam undergoes glucuronidation, which is preserved in liver disease, while
diazepam requires oxidation [CORRECT]
B. Lorazepam has higher oral bioavailability than diazepam
C. Lorazepam is renally eliminated and unaffected by liver function
D. Lorazepam has a larger volume of distribution in cirrhosis
Correct Answer: A
Rationale: In severe liver disease (cirrhosis, hepatitis), Phase I reactions (oxidation,
reduction, hydrolysis via CYP450 enzymes) are significantly impaired due to hepatocyte
damage and reduced enzyme content. Phase II reactions (glucuronidation, sulfation,
acetylation) are relatively preserved until very advanced disease. Diazepam undergoes
