Chamberlain University
NR-283
Pathophysiology Exam
Section 1: Foundational Principles - Pharmacokinetics and
Pharmacodynamics (Questions 1-25)
1. Which term describes what the BODY does to a drug?
A. Pharmacodynamics
B. Pharmacotherapeutics
C. Pharmacokinetics
D. Pharmacognosy
Rationale: Pharmacokinetics is the study of what the body does to a drug, including the
four processes of absorption, distribution, metabolism, and excretion (ADME).
Understanding pharmacokinetics allows nurses to predict drug concentrations at the
site of action, determine appropriate dosing intervals, and anticipate potential drug
interactions.
2. Which term describes what the DRUG does to the body?
A. Pharmacokinetics
B. Pharmacodynamics
C. Pharmacognosy
D. Pharmacotherapeutics
,Rationale: Pharmacodynamics is the study of what the drug does to the body—the
biochemical and physiological effects of drugs and their mechanisms of action,
including receptor binding and dose-response relationships.
3. The "first-pass effect" refers to:
A. The drug being metabolized by the liver before reaching systemic circulation
B. The drug binding to plasma proteins
C. The drug being excreted by the kidneys
D. The drug crossing the blood-brain barrier
Rationale: The first-pass effect (presystemic metabolism) occurs when a drug is
extensively metabolized by the liver or gut wall before it reaches systemic circulation
after oral administration. This significantly reduces the drug's bioavailability.
4. Bioavailability is defined as:
A. The total amount of drug administered to a patient
B. The fraction of an administered dose of unchanged drug that reaches the
systemic circulation
C. The speed at which a drug is metabolized by the liver
D. The degree to which a drug binds to plasma proteins
Rationale: Bioavailability is the extent of drug absorption for a given drug and route—
the amount of active drug that reaches systemic circulation. For intravenously
administered drugs, bioavailability is 100% (F = 1.0).
5. A drug that binds to a receptor and produces a response is called a(n):
A. Antagonist
B. Agonist
C. Enzyme
D. Inhibitor
,Rationale: An agonist is a drug that binds to a receptor and activates it, producing a
biological response. An antagonist binds to a receptor without activating it, thereby
blocking the action of agonists or endogenous substances.
6. What is the meaning of a drug's half-life (t1/2)?
A. The time it takes for a drug to reach its peak concentration in the blood
B. The time it takes for the plasma concentration of a drug to decrease by half
C. The duration of time a drug produces its therapeutic effect
D. The time required for a drug to be completely eliminated from the body
Rationale: The half-life of a drug is the time required for the plasma concentration of
the drug to decrease by 50% after distribution equilibrium is reached. It takes
approximately 4-5 half-lives for a drug to reach steady state with repeated dosing.
7. If a drug has a half-life of 4 hours, what percentage of the drug will remain in
the body after 8 hours?
A. 50%
B. 25%
C. 12.5%
D. 0%
Rationale: After 4 hours (1 half-life), 50% remains. After 8 hours (2 half-lives), 25%
remains. Each half-life reduces the remaining drug by 50%.
8. Which route of administration has the FASTEST onset of action?
A. Oral
B. Subcutaneous
C. Intramuscular
D. Intravenous
, Rationale: IV administration delivers the drug directly into the bloodstream, providing
the fastest onset of action. Oral, IM, and SQ routes require absorption before the drug
reaches systemic circulation.
9. A patient is taking a drug that is a substrate of the cytochrome P450 3A4
enzyme. If the patient begins taking a known CYP3A4 inhibitor, what effect would
be expected?
A. Decreased therapeutic effect of the substrate drug
B. Increased metabolism and decreased levels of the substrate drug
C. Increased levels and potential toxicity of the substrate drug
D. No change in the substrate drug levels
Rationale: A CYP3A4 inhibitor reduces the metabolic activity of the CYP3A enzyme,
leading to decreased metabolism of substrate drugs that depend on this enzyme for
breakdown. This results in increased plasma levels of the substrate drug, which can lead
to enhanced therapeutic effects or toxicity.
10. Which serum protein is the most important for binding drug molecules in the
blood?
A. Albumin
B. Hemoglobin
C. Globulin
D. Fibrinogen
Rationale: Albumin is the most common blood protein and carries the majority of
protein-bound drug molecules. Low albumin levels can increase free drug levels and risk
of toxicity.
11. What is a narrow therapeutic index?
NR-283
Pathophysiology Exam
Section 1: Foundational Principles - Pharmacokinetics and
Pharmacodynamics (Questions 1-25)
1. Which term describes what the BODY does to a drug?
A. Pharmacodynamics
B. Pharmacotherapeutics
C. Pharmacokinetics
D. Pharmacognosy
Rationale: Pharmacokinetics is the study of what the body does to a drug, including the
four processes of absorption, distribution, metabolism, and excretion (ADME).
Understanding pharmacokinetics allows nurses to predict drug concentrations at the
site of action, determine appropriate dosing intervals, and anticipate potential drug
interactions.
2. Which term describes what the DRUG does to the body?
A. Pharmacokinetics
B. Pharmacodynamics
C. Pharmacognosy
D. Pharmacotherapeutics
,Rationale: Pharmacodynamics is the study of what the drug does to the body—the
biochemical and physiological effects of drugs and their mechanisms of action,
including receptor binding and dose-response relationships.
3. The "first-pass effect" refers to:
A. The drug being metabolized by the liver before reaching systemic circulation
B. The drug binding to plasma proteins
C. The drug being excreted by the kidneys
D. The drug crossing the blood-brain barrier
Rationale: The first-pass effect (presystemic metabolism) occurs when a drug is
extensively metabolized by the liver or gut wall before it reaches systemic circulation
after oral administration. This significantly reduces the drug's bioavailability.
4. Bioavailability is defined as:
A. The total amount of drug administered to a patient
B. The fraction of an administered dose of unchanged drug that reaches the
systemic circulation
C. The speed at which a drug is metabolized by the liver
D. The degree to which a drug binds to plasma proteins
Rationale: Bioavailability is the extent of drug absorption for a given drug and route—
the amount of active drug that reaches systemic circulation. For intravenously
administered drugs, bioavailability is 100% (F = 1.0).
5. A drug that binds to a receptor and produces a response is called a(n):
A. Antagonist
B. Agonist
C. Enzyme
D. Inhibitor
,Rationale: An agonist is a drug that binds to a receptor and activates it, producing a
biological response. An antagonist binds to a receptor without activating it, thereby
blocking the action of agonists or endogenous substances.
6. What is the meaning of a drug's half-life (t1/2)?
A. The time it takes for a drug to reach its peak concentration in the blood
B. The time it takes for the plasma concentration of a drug to decrease by half
C. The duration of time a drug produces its therapeutic effect
D. The time required for a drug to be completely eliminated from the body
Rationale: The half-life of a drug is the time required for the plasma concentration of
the drug to decrease by 50% after distribution equilibrium is reached. It takes
approximately 4-5 half-lives for a drug to reach steady state with repeated dosing.
7. If a drug has a half-life of 4 hours, what percentage of the drug will remain in
the body after 8 hours?
A. 50%
B. 25%
C. 12.5%
D. 0%
Rationale: After 4 hours (1 half-life), 50% remains. After 8 hours (2 half-lives), 25%
remains. Each half-life reduces the remaining drug by 50%.
8. Which route of administration has the FASTEST onset of action?
A. Oral
B. Subcutaneous
C. Intramuscular
D. Intravenous
, Rationale: IV administration delivers the drug directly into the bloodstream, providing
the fastest onset of action. Oral, IM, and SQ routes require absorption before the drug
reaches systemic circulation.
9. A patient is taking a drug that is a substrate of the cytochrome P450 3A4
enzyme. If the patient begins taking a known CYP3A4 inhibitor, what effect would
be expected?
A. Decreased therapeutic effect of the substrate drug
B. Increased metabolism and decreased levels of the substrate drug
C. Increased levels and potential toxicity of the substrate drug
D. No change in the substrate drug levels
Rationale: A CYP3A4 inhibitor reduces the metabolic activity of the CYP3A enzyme,
leading to decreased metabolism of substrate drugs that depend on this enzyme for
breakdown. This results in increased plasma levels of the substrate drug, which can lead
to enhanced therapeutic effects or toxicity.
10. Which serum protein is the most important for binding drug molecules in the
blood?
A. Albumin
B. Hemoglobin
C. Globulin
D. Fibrinogen
Rationale: Albumin is the most common blood protein and carries the majority of
protein-bound drug molecules. Low albumin levels can increase free drug levels and risk
of toxicity.
11. What is a narrow therapeutic index?
