NUR-641E Advanced Pathophysiology and Pharmacology –
2026/2027 Academic Year – Comprehensive Midterm
SECTION I: PHARMACOKINETICS & PHARMACODYNAMICS
Questions 1–20
1. A nurse educator is teaching about the factors that affect drug bioavailability.
Which statement by a student indicates a need for further teaching?
A. "Bioavailability is influenced by the drug's chemical stability and solubility."
B. "First-pass metabolism in the liver significantly reduces the bioavailability of
orally administered drugs."
C. "Intravenous administration provides 100% bioavailability because it bypasses
absorption."
D. "Bioequivalence between two formulations guarantees identical bioavailability
in all patients."
A. Bioavailability is influenced by the drug's chemical stability and solubility.
B. First-pass metabolism in the liver significantly reduces the bioavailability of
orally administered drugs.
C. Intravenous administration provides 100% bioavailability because it
bypasses absorption.
D. Bioequivalence between two formulations guarantees identical
bioavailability in all patients.
Correct Answer: D
Rationale: Bioequivalence refers to the relative therapeutic effectiveness of
chemically equivalent drugs. However, bioequivalence does not guarantee
identical bioavailability in all patients, as bioavailability is affected by chemical
instability, solubility, and first-pass metabolism. Factors such as gastrointestinal
motility, food interactions, and individual patient variations can affect drug
absorption even between bioequivalent formulations.
,2. A patient has been taking a medication with a half-life of 8 hours.
Approximately how long will it take for this drug to reach steady state?
A. 16 hours
B. 24 hours
C. 32–40 hours
D. 48–56 hours
A. 16 hours
B. 24 hours
C. 32–40 hours
D. 48–56 hours
Correct Answer: C
Rationale: Steady state is usually reached within 4–5 half-lives of a drug. With a
half-life of 8 hours, steady state would be achieved in approximately 32–40 hours
(4 × 8 = 32 hours to 5 × 8 = 40 hours). At steady state, the rate of drug
administration equals the rate of drug elimination.
3. Which of the following statements accurately describes zero-order
(nonlinear) pharmacokinetics?
A. The drug is metabolized at a rate proportional to its concentration.
B. A constant fraction of the drug is eliminated per unit time.
C. The drug is metabolized at a constant rate per unit time regardless of
concentration.
D. The half-life remains constant regardless of the dose administered.
A. The drug is metabolized at a rate proportional to its concentration.
B. A constant fraction of the drug is eliminated per unit time.
C. The drug is metabolized at a constant rate per unit time regardless of
concentration.
D. The half-life remains constant regardless of the dose administered.
Correct Answer: C
,Rationale: Zero-order (nonlinear) pharmacokinetics means a drug is metabolized
at a constant rate per unit time. Unlike first-order kinetics where a constant
fraction is eliminated, zero-order kinetics involve saturation of metabolic
pathways, resulting in a constant amount being eliminated regardless of drug
concentration. Examples include phenytoin, aspirin (at high doses), and ethanol.
4. A patient is prescribed a drug that is a CYP3A4 substrate. Which concurrent
medication would most likely increase the levels of this drug and potentially
cause toxicity?
A. A CYP3A4 inducer
B. A CYP3A4 inhibitor
C. A drug with the same mechanism of action
D. A drug with a different metabolic pathway
A. A CYP3A4 inducer
B. A CYP3A4 inhibitor
C. A drug with the same mechanism of action
D. A drug with a different metabolic pathway
Correct Answer: B
Rationale: A CYP3A4 inhibitor decreases the metabolism of a substrate, resulting
in an increased level or effect of the substrate. CYP3A4 substrate drugs may have
enhanced activity if any CYP3A4 inducer drugs are used along with them, but
inhibitors will increase drug levels further. Common CYP3A4 inhibitors include
grapefruit juice, ketoconazole, and erythromycin.
5. A nurse is reviewing the route of administration with the highest
bioavailability. Which route should the nurse identify?
A. Oral
B. Sublingual
C. Intramuscular
D. Intravenous
, A. Oral
B. Sublingual
C. Intramuscular
D. Intravenous
Correct Answer: D
Rationale: The intravenous route has the highest bioavailability because the
entire dose is placed directly into the patient's vein, bypassing the absorption
phase entirely. The IV route also avoids first-pass metabolism in the liver. Oral
administration is subject to first-pass metabolism, and rectal administration has
variable and erratic absorption.
6. A patient is taking warfarin for atrial fibrillation. The prescriber adds
omeprazole for GERD. What interaction should the nurse anticipate?
A. Increased warfarin effect due to competition for CYP2C19 metabolism
B. Decreased warfarin effect due to increased metabolism
C. No significant interaction
D. Increased warfarin effect due to protein binding displacement
A. Increased warfarin effect due to competition for CYP2C19 metabolism
B. Decreased warfarin effect due to increased metabolism
C. No significant interaction
D. Increased warfarin effect due to protein binding displacement
Correct Answer: A
Rationale: Warfarin is metabolized by CYP2C19, and omeprazole is a CYP2C19
inhibitor. When these drugs are taken together, there is competition for enzyme
metabolism, leading to higher warfarin levels and increased anticoagulant effect.
This interaction places the patient at increased risk for bleeding complications.
7. A nurse educator is explaining drug distribution to nursing students. Which
factor has the GREATEST impact on drug distribution?
2026/2027 Academic Year – Comprehensive Midterm
SECTION I: PHARMACOKINETICS & PHARMACODYNAMICS
Questions 1–20
1. A nurse educator is teaching about the factors that affect drug bioavailability.
Which statement by a student indicates a need for further teaching?
A. "Bioavailability is influenced by the drug's chemical stability and solubility."
B. "First-pass metabolism in the liver significantly reduces the bioavailability of
orally administered drugs."
C. "Intravenous administration provides 100% bioavailability because it bypasses
absorption."
D. "Bioequivalence between two formulations guarantees identical bioavailability
in all patients."
A. Bioavailability is influenced by the drug's chemical stability and solubility.
B. First-pass metabolism in the liver significantly reduces the bioavailability of
orally administered drugs.
C. Intravenous administration provides 100% bioavailability because it
bypasses absorption.
D. Bioequivalence between two formulations guarantees identical
bioavailability in all patients.
Correct Answer: D
Rationale: Bioequivalence refers to the relative therapeutic effectiveness of
chemically equivalent drugs. However, bioequivalence does not guarantee
identical bioavailability in all patients, as bioavailability is affected by chemical
instability, solubility, and first-pass metabolism. Factors such as gastrointestinal
motility, food interactions, and individual patient variations can affect drug
absorption even between bioequivalent formulations.
,2. A patient has been taking a medication with a half-life of 8 hours.
Approximately how long will it take for this drug to reach steady state?
A. 16 hours
B. 24 hours
C. 32–40 hours
D. 48–56 hours
A. 16 hours
B. 24 hours
C. 32–40 hours
D. 48–56 hours
Correct Answer: C
Rationale: Steady state is usually reached within 4–5 half-lives of a drug. With a
half-life of 8 hours, steady state would be achieved in approximately 32–40 hours
(4 × 8 = 32 hours to 5 × 8 = 40 hours). At steady state, the rate of drug
administration equals the rate of drug elimination.
3. Which of the following statements accurately describes zero-order
(nonlinear) pharmacokinetics?
A. The drug is metabolized at a rate proportional to its concentration.
B. A constant fraction of the drug is eliminated per unit time.
C. The drug is metabolized at a constant rate per unit time regardless of
concentration.
D. The half-life remains constant regardless of the dose administered.
A. The drug is metabolized at a rate proportional to its concentration.
B. A constant fraction of the drug is eliminated per unit time.
C. The drug is metabolized at a constant rate per unit time regardless of
concentration.
D. The half-life remains constant regardless of the dose administered.
Correct Answer: C
,Rationale: Zero-order (nonlinear) pharmacokinetics means a drug is metabolized
at a constant rate per unit time. Unlike first-order kinetics where a constant
fraction is eliminated, zero-order kinetics involve saturation of metabolic
pathways, resulting in a constant amount being eliminated regardless of drug
concentration. Examples include phenytoin, aspirin (at high doses), and ethanol.
4. A patient is prescribed a drug that is a CYP3A4 substrate. Which concurrent
medication would most likely increase the levels of this drug and potentially
cause toxicity?
A. A CYP3A4 inducer
B. A CYP3A4 inhibitor
C. A drug with the same mechanism of action
D. A drug with a different metabolic pathway
A. A CYP3A4 inducer
B. A CYP3A4 inhibitor
C. A drug with the same mechanism of action
D. A drug with a different metabolic pathway
Correct Answer: B
Rationale: A CYP3A4 inhibitor decreases the metabolism of a substrate, resulting
in an increased level or effect of the substrate. CYP3A4 substrate drugs may have
enhanced activity if any CYP3A4 inducer drugs are used along with them, but
inhibitors will increase drug levels further. Common CYP3A4 inhibitors include
grapefruit juice, ketoconazole, and erythromycin.
5. A nurse is reviewing the route of administration with the highest
bioavailability. Which route should the nurse identify?
A. Oral
B. Sublingual
C. Intramuscular
D. Intravenous
, A. Oral
B. Sublingual
C. Intramuscular
D. Intravenous
Correct Answer: D
Rationale: The intravenous route has the highest bioavailability because the
entire dose is placed directly into the patient's vein, bypassing the absorption
phase entirely. The IV route also avoids first-pass metabolism in the liver. Oral
administration is subject to first-pass metabolism, and rectal administration has
variable and erratic absorption.
6. A patient is taking warfarin for atrial fibrillation. The prescriber adds
omeprazole for GERD. What interaction should the nurse anticipate?
A. Increased warfarin effect due to competition for CYP2C19 metabolism
B. Decreased warfarin effect due to increased metabolism
C. No significant interaction
D. Increased warfarin effect due to protein binding displacement
A. Increased warfarin effect due to competition for CYP2C19 metabolism
B. Decreased warfarin effect due to increased metabolism
C. No significant interaction
D. Increased warfarin effect due to protein binding displacement
Correct Answer: A
Rationale: Warfarin is metabolized by CYP2C19, and omeprazole is a CYP2C19
inhibitor. When these drugs are taken together, there is competition for enzyme
metabolism, leading to higher warfarin levels and increased anticoagulant effect.
This interaction places the patient at increased risk for bleeding complications.
7. A nurse educator is explaining drug distribution to nursing students. Which
factor has the GREATEST impact on drug distribution?
