NURS 251 Final Exam V3 | NURS 251 Final
Exam – Pharmacology | Portage | Q&A with
Rationale (Portage NURS 251 Final Exam)
1. Which pharmacokinetics phase is primarily affected when a patient has significant hepatic
impairment?
A. Absorption
B. Distribution
C. Excretion
D. Metabolism
Answer: D
Rationale: The liver is the primary organ responsible for the metabolic breakdown of
medications through enzyme systems like Cytochrome P450. When hepatic function is
impaired, the body cannot effectively chemically alter drugs for inactivation or elimination.
This can lead to increased drug levels in the bloodstream and a higher risk for toxicity.
2. A nurse is administering a drug with a high first-pass effect. Which route of administration
would result in the lowest bioavailability?
A. Intravenous
B. Sublingual
C. Oral
,D. Intramuscular
Answer: C
Rationale: The first-pass effect occurs when a drug is absorbed from the GI tract and
enters the portal circulation to the liver before reaching systemic circulation. Medications
taken orally are subject to this process, which significantly reduces the active concentration
of the drug. Other routes like IV or sublingual bypass the liver initially, ensuring higher
bioavailability.
3. What is the primary goal of administering a loading dose of a medication?
A. To reach a therapeutic steady state more quickly
B. To reduce the risk of side effects
C. To bypass the first-pass effect
D. To ensure the drug is excreted rapidly
Answer: A
Rationale: A loading dose is a larger-than-normal initial dose given to rapidly achieve a
therapeutic concentration in the plasma. This is often used for drugs with long half-lives
that would otherwise take days to reach steady state. By starting with a higher amount, the
patient receives clinical benefits of the medication much sooner.
4. Which serum protein is most commonly responsible for drug binding and distribution in the
blood?
A. Albumin
, B. Hemoglobin
C. Gamma globulin
D. Fibrinogen
Answer: A
Rationale: Albumin is the most prevalent protein in the plasma and serves as the primary
carrier for many acidic drugs. Only the ‘free’ or unbound portion of a drug is
pharmacologically active and able to cross cell membranes. Patients with low albumin
levels, such as those with malnutrition, are at increased risk for drug toxicity due to higher
levels of free drug.
5. A drug that mimics the action of a natural neurotransmitter by binding to a receptor is
known as a(n):
A. Antagonist
B. Agonist
C. Inhibitor
D. Blocker
Answer: B
Rationale: An agonist is a molecule that binds to a receptor and activates it to produce a
biological response. This contrasts with an antagonist, which binds to a receptor but
Exam – Pharmacology | Portage | Q&A with
Rationale (Portage NURS 251 Final Exam)
1. Which pharmacokinetics phase is primarily affected when a patient has significant hepatic
impairment?
A. Absorption
B. Distribution
C. Excretion
D. Metabolism
Answer: D
Rationale: The liver is the primary organ responsible for the metabolic breakdown of
medications through enzyme systems like Cytochrome P450. When hepatic function is
impaired, the body cannot effectively chemically alter drugs for inactivation or elimination.
This can lead to increased drug levels in the bloodstream and a higher risk for toxicity.
2. A nurse is administering a drug with a high first-pass effect. Which route of administration
would result in the lowest bioavailability?
A. Intravenous
B. Sublingual
C. Oral
,D. Intramuscular
Answer: C
Rationale: The first-pass effect occurs when a drug is absorbed from the GI tract and
enters the portal circulation to the liver before reaching systemic circulation. Medications
taken orally are subject to this process, which significantly reduces the active concentration
of the drug. Other routes like IV or sublingual bypass the liver initially, ensuring higher
bioavailability.
3. What is the primary goal of administering a loading dose of a medication?
A. To reach a therapeutic steady state more quickly
B. To reduce the risk of side effects
C. To bypass the first-pass effect
D. To ensure the drug is excreted rapidly
Answer: A
Rationale: A loading dose is a larger-than-normal initial dose given to rapidly achieve a
therapeutic concentration in the plasma. This is often used for drugs with long half-lives
that would otherwise take days to reach steady state. By starting with a higher amount, the
patient receives clinical benefits of the medication much sooner.
4. Which serum protein is most commonly responsible for drug binding and distribution in the
blood?
A. Albumin
, B. Hemoglobin
C. Gamma globulin
D. Fibrinogen
Answer: A
Rationale: Albumin is the most prevalent protein in the plasma and serves as the primary
carrier for many acidic drugs. Only the ‘free’ or unbound portion of a drug is
pharmacologically active and able to cross cell membranes. Patients with low albumin
levels, such as those with malnutrition, are at increased risk for drug toxicity due to higher
levels of free drug.
5. A drug that mimics the action of a natural neurotransmitter by binding to a receptor is
known as a(n):
A. Antagonist
B. Agonist
C. Inhibitor
D. Blocker
Answer: B
Rationale: An agonist is a molecule that binds to a receptor and activates it to produce a
biological response. This contrasts with an antagonist, which binds to a receptor but
