West Coast University NURS 180 Week 2 Quiz (pdf) |
2026/2027 | Gastrointestinal & Foundational Pharmacology
Q&A | Nursing
1. Which term describes the percentage of an administered drug dose that reaches the
systemic circulation in an unchanged form?
A) Distribution
B) Bioavailability
C) Metabolism
D) Excretion
Correct Answer: Bioavailability
Rationale: Bioavailability represents the fraction of an administered drug dose that reaches systemic
circulation in its active form. Intravenous administration provides 100% bioavailability because it
bypasses absorption barriers. The other options represent different pharmacokinetic processes:
distribution, metabolism, and excretion. Therefore, bioavailability is the correct term for this concept.
2. The first-pass effect primarily occurs with which route of administration?
A) Intravenous
B) Intramuscular
C) Oral
D) Sublingual
Correct Answer: Oral
Rationale: Orally administered drugs are absorbed from the gastrointestinal tract and transported via
the portal vein to the liver, where they undergo metabolism before reaching systemic circulation. This
hepatic metabolism reduces the amount of active drug that reaches target tissues. Sublingual,
intravenous, and intramuscular routes bypass this initial hepatic metabolism. Therefore, the oral
route is most associated with the first-pass effect.
3. What is the primary site of drug metabolism in the human body?
A) Kidneys
B) Lungs
C) Liver
D) Stomach
Correct Answer: Liver
Rationale: The liver is the primary organ responsible for drug metabolism, utilizing the cytochrome
P450 enzyme system to chemically alter drug structures. This biotransformation converts drugs into
metabolites that can be more readily excreted. While the kidneys are the primary site of excretion,
they are not the main site of metabolism. Therefore, the liver is the correct answer.
4. A drug with a narrow therapeutic index indicates which of the following?
A) The drug is very safe and requires minimal monitoring
B) The difference between therapeutic and toxic doses is small
C) The drug has a very long half-life
D) The drug is highly protein-bound
,Correct Answer: The difference between therapeutic and toxic doses is small
Rationale: A narrow therapeutic index means there is a small margin between the dose that produces
therapeutic effects and the dose that produces toxic effects. Drugs such as digoxin and warfarin have
narrow therapeutic indices and require careful serum level monitoring. This characteristic does not
indicate safety, half-life, or protein binding. Therefore, a narrow therapeutic index specifically
describes a small difference between effective and toxic doses.
5. Which organ is primarily responsible for the excretion of drugs and their metabolites?
A) Liver
B) Kidneys
C) Lungs
D) Skin
Correct Answer: Kidneys
Rationale: The kidneys are the primary organs of drug excretion, filtering drugs and metabolites from
the bloodstream into urine. While the liver metabolizes drugs and the lungs and skin can eliminate
certain substances, renal excretion is the major route for most medications. Therefore, the kidneys
are the correct answer for the primary site of drug elimination.
6. A drug that binds to a receptor and produces a biological response is called a(n):
A) Antagonist
B) Inhibitor
C) Agonist
D) Blocker
Correct Answer: Agonist
Rationale: An agonist is a drug that binds to a receptor and activates it, producing a biological
response that mimics the body's natural regulatory molecules. In contrast, antagonists bind to
receptors but do not activate them; they block the effects of agonists. Inhibitors and blockers are not
standard pharmacologic terms for receptor activation. Therefore, an agonist is the correct term for a
drug that stimulates a receptor.
7. What occurs when two drugs with similar actions are taken together, resulting in an effect
equal to the sum of their individual effects?
A) Additive effect
B) Synergistic effect
C) Antagonistic effect
D) Potentiation
Correct Answer: Additive effect
Rationale: An additive effect occurs when two drugs with similar mechanisms or actions are
combined, producing a cumulative effect equal to the sum of their individual effects (1 + 1 = 2). A
synergistic effect produces a greater-than-additive response, while antagonism reduces the effect of
one drug by another. Potentiation occurs when one drug enhances the effect of another without
having the effect itself. Therefore, additive effect is the correct description.
8. Which factor is most likely to decrease the rate of drug metabolism in an elderly patient?
A) Increased body fat percentage
B) Decreased liver enzyme activity
, C) Increased glomerular filtration rate
D) Decreased gastric pH
Correct Answer: Decreased liver enzyme activity
Rationale: Aging is associated with a decline in hepatic enzyme activity and reduced liver blood flow,
which slows drug metabolism and prolongs drug effects. While increased body fat affects drug
distribution, the question specifically addresses metabolism. Increased glomerular filtration would
enhance excretion, not metabolism, and decreased gastric pH is not a typical aging change.
Therefore, decreased liver enzyme activity is the primary factor reducing drug metabolism in elderly
patients.
9. A nurse is caring for a patient with low serum albumin who is prescribed a highly protein-
bound drug. Which outcome is most likely?
A) Decreased drug absorption
B) Increased risk of drug toxicity
C) Enhanced drug excretion
D) Reduced therapeutic effect
Correct Answer: Increased risk of drug toxicity
Rationale: Highly protein-bound drugs bind to albumin in the bloodstream, leaving only the unbound
(free) fraction pharmacologically active. When albumin levels are low, more free drug circulates,
increasing the risk of toxicity even at standard doses. Absorption and excretion are not directly
affected by protein binding in this scenario. Therefore, low albumin increases the risk of drug toxicity
due to elevated free drug levels.
10. Which route of administration provides 100% bioavailability?
A) Oral
B) Intravenous
C) Intramuscular
D) Subcutaneous
Correct Answer: Intravenous
Rationale: Intravenous administration bypasses absorption barriers and the first-pass effect,
delivering the full drug dose directly into the systemic circulation. Oral, intramuscular, and
subcutaneous routes all involve absorption processes that reduce bioavailability to varying degrees.
Therefore, intravenous administration is the only route that consistently provides 100%
bioavailability.
11. What is the primary mechanism of action of proton pump inhibitors?
A) Blocking H2 receptors in the stomach
B) Neutralizing gastric acid directly
C) Irreversibly inhibiting the H+/K+-ATPase pump
D) Forming a protective barrier over ulcers
Correct Answer: Irreversibly inhibiting the H+/K+-ATPase pump
Rationale: Proton pump inhibitors such as omeprazole work by irreversibly inhibiting the H+/K+-
ATPase enzyme in gastric parietal cells, which is the final common pathway for acid secretion. H2
receptor antagonists work through a different mechanism by blocking histamine receptors. Antacids
2026/2027 | Gastrointestinal & Foundational Pharmacology
Q&A | Nursing
1. Which term describes the percentage of an administered drug dose that reaches the
systemic circulation in an unchanged form?
A) Distribution
B) Bioavailability
C) Metabolism
D) Excretion
Correct Answer: Bioavailability
Rationale: Bioavailability represents the fraction of an administered drug dose that reaches systemic
circulation in its active form. Intravenous administration provides 100% bioavailability because it
bypasses absorption barriers. The other options represent different pharmacokinetic processes:
distribution, metabolism, and excretion. Therefore, bioavailability is the correct term for this concept.
2. The first-pass effect primarily occurs with which route of administration?
A) Intravenous
B) Intramuscular
C) Oral
D) Sublingual
Correct Answer: Oral
Rationale: Orally administered drugs are absorbed from the gastrointestinal tract and transported via
the portal vein to the liver, where they undergo metabolism before reaching systemic circulation. This
hepatic metabolism reduces the amount of active drug that reaches target tissues. Sublingual,
intravenous, and intramuscular routes bypass this initial hepatic metabolism. Therefore, the oral
route is most associated with the first-pass effect.
3. What is the primary site of drug metabolism in the human body?
A) Kidneys
B) Lungs
C) Liver
D) Stomach
Correct Answer: Liver
Rationale: The liver is the primary organ responsible for drug metabolism, utilizing the cytochrome
P450 enzyme system to chemically alter drug structures. This biotransformation converts drugs into
metabolites that can be more readily excreted. While the kidneys are the primary site of excretion,
they are not the main site of metabolism. Therefore, the liver is the correct answer.
4. A drug with a narrow therapeutic index indicates which of the following?
A) The drug is very safe and requires minimal monitoring
B) The difference between therapeutic and toxic doses is small
C) The drug has a very long half-life
D) The drug is highly protein-bound
,Correct Answer: The difference between therapeutic and toxic doses is small
Rationale: A narrow therapeutic index means there is a small margin between the dose that produces
therapeutic effects and the dose that produces toxic effects. Drugs such as digoxin and warfarin have
narrow therapeutic indices and require careful serum level monitoring. This characteristic does not
indicate safety, half-life, or protein binding. Therefore, a narrow therapeutic index specifically
describes a small difference between effective and toxic doses.
5. Which organ is primarily responsible for the excretion of drugs and their metabolites?
A) Liver
B) Kidneys
C) Lungs
D) Skin
Correct Answer: Kidneys
Rationale: The kidneys are the primary organs of drug excretion, filtering drugs and metabolites from
the bloodstream into urine. While the liver metabolizes drugs and the lungs and skin can eliminate
certain substances, renal excretion is the major route for most medications. Therefore, the kidneys
are the correct answer for the primary site of drug elimination.
6. A drug that binds to a receptor and produces a biological response is called a(n):
A) Antagonist
B) Inhibitor
C) Agonist
D) Blocker
Correct Answer: Agonist
Rationale: An agonist is a drug that binds to a receptor and activates it, producing a biological
response that mimics the body's natural regulatory molecules. In contrast, antagonists bind to
receptors but do not activate them; they block the effects of agonists. Inhibitors and blockers are not
standard pharmacologic terms for receptor activation. Therefore, an agonist is the correct term for a
drug that stimulates a receptor.
7. What occurs when two drugs with similar actions are taken together, resulting in an effect
equal to the sum of their individual effects?
A) Additive effect
B) Synergistic effect
C) Antagonistic effect
D) Potentiation
Correct Answer: Additive effect
Rationale: An additive effect occurs when two drugs with similar mechanisms or actions are
combined, producing a cumulative effect equal to the sum of their individual effects (1 + 1 = 2). A
synergistic effect produces a greater-than-additive response, while antagonism reduces the effect of
one drug by another. Potentiation occurs when one drug enhances the effect of another without
having the effect itself. Therefore, additive effect is the correct description.
8. Which factor is most likely to decrease the rate of drug metabolism in an elderly patient?
A) Increased body fat percentage
B) Decreased liver enzyme activity
, C) Increased glomerular filtration rate
D) Decreased gastric pH
Correct Answer: Decreased liver enzyme activity
Rationale: Aging is associated with a decline in hepatic enzyme activity and reduced liver blood flow,
which slows drug metabolism and prolongs drug effects. While increased body fat affects drug
distribution, the question specifically addresses metabolism. Increased glomerular filtration would
enhance excretion, not metabolism, and decreased gastric pH is not a typical aging change.
Therefore, decreased liver enzyme activity is the primary factor reducing drug metabolism in elderly
patients.
9. A nurse is caring for a patient with low serum albumin who is prescribed a highly protein-
bound drug. Which outcome is most likely?
A) Decreased drug absorption
B) Increased risk of drug toxicity
C) Enhanced drug excretion
D) Reduced therapeutic effect
Correct Answer: Increased risk of drug toxicity
Rationale: Highly protein-bound drugs bind to albumin in the bloodstream, leaving only the unbound
(free) fraction pharmacologically active. When albumin levels are low, more free drug circulates,
increasing the risk of toxicity even at standard doses. Absorption and excretion are not directly
affected by protein binding in this scenario. Therefore, low albumin increases the risk of drug toxicity
due to elevated free drug levels.
10. Which route of administration provides 100% bioavailability?
A) Oral
B) Intravenous
C) Intramuscular
D) Subcutaneous
Correct Answer: Intravenous
Rationale: Intravenous administration bypasses absorption barriers and the first-pass effect,
delivering the full drug dose directly into the systemic circulation. Oral, intramuscular, and
subcutaneous routes all involve absorption processes that reduce bioavailability to varying degrees.
Therefore, intravenous administration is the only route that consistently provides 100%
bioavailability.
11. What is the primary mechanism of action of proton pump inhibitors?
A) Blocking H2 receptors in the stomach
B) Neutralizing gastric acid directly
C) Irreversibly inhibiting the H+/K+-ATPase pump
D) Forming a protective barrier over ulcers
Correct Answer: Irreversibly inhibiting the H+/K+-ATPase pump
Rationale: Proton pump inhibitors such as omeprazole work by irreversibly inhibiting the H+/K+-
ATPase enzyme in gastric parietal cells, which is the final common pathway for acid secretion. H2
receptor antagonists work through a different mechanism by blocking histamine receptors. Antacids
