NSG 1540 Pharmacotherapeutics
Final Practice Exam 100 Questions
with Correct Answers and Detailed
Rationales
INSTRUCTIONS:
This comprehensive practice exam covers key pharmacotherapeutic
concepts for nursing students. Each question includes the correct
answer and a detailed rationale explaining the underlying
pharmacology, nursing implications, and clinical decision-making. Use
this to prepare for your NSG 1540 final examination.
SECTION 1: Fundamental Pharmacology
Principles (Questions 1-15)
Question 1:
A nurse is preparing to administer a medication that has a half-life of 4
hours. After 24 hours, approximately what percentage of the drug
remains in the patient's body?
A) 50%
B) 25%
C) 6.25%
D) 1.56%
Correct Answer: D) 1.56%
,Rationale: After one half-life (4 hours), 50% remains. After 2 half-lives
(8 hours), 25% remains. After 3 half-lives (12 hours), 12.5% remains.
After 4 half-lives (16 hours), 6.25% remains. After 5 half-lives (20
hours), 3.125% remains. After 6 half-lives (24 hours), approximately
1.56% remains. This concept is critical for understanding drug
elimination, dosing intervals, and time to steady state (typically 4-5
half-lives). Nurses must understand half-life to monitor drug
accumulation and toxicity.
Question 2:
A patient with liver disease is prescribed a medication that undergoes
extensive first-pass metabolism. The nurse anticipates that the
prescriber may need to:
A) Increase the oral dose
B) Decrease the oral dose
C) Administer the medication by a different route to bypass first-pass
effect
D) Increase the frequency of administration
Correct Answer: C) Administer the medication by a different route to
bypass first-pass effect
Rationale: First-pass metabolism occurs when drugs are absorbed
from the GI tract and metabolized by the liver before reaching
systemic circulation. In liver disease, metabolism is impaired, leading
to higher bioavailability and potential toxicity. Administering the drug
via a route that bypasses the liver (e.g., sublingual, IV, transdermal)
avoids first-pass metabolism. Option A (increasing oral dose) would
worsen toxicity. Option B (decreasing oral dose) might be considered,
but route change is the most definitive. Option D (increasing
frequency) would also worsen toxicity. This is a key concept in
pharmacokinetics for patients with hepatic impairment.
,Question 3:
The nurse understands that the therapeutic index of a drug is a
measure of:
A) The drug's potency
B) The drug's efficacy
C) The drug's safety margin
D) The drug's absorption rate
Correct Answer: C) The drug's safety margin
Rationale: The therapeutic index (TI) is the ratio of the lethal dose
(LD50) to the effective dose (ED50) or the toxic dose (TD50) to the
effective dose. A high TI indicates a wide margin of safety (e.g.,
penicillin), while a low TI indicates a narrow margin (e.g., digoxin,
lithium, warfarin). Option A (potency) refers to the amount of drug
needed to produce an effect. Option B (efficacy) refers to the
maximum effect a drug can achieve. Option D (absorption) is a
pharmacokinetic property. Understanding TI helps nurses identify
drugs requiring close monitoring of serum levels and adverse effects.
Question 4:
A patient is receiving a drug that is 95% protein-bound. Which
statement best describes the clinical significance of this?
A) The drug will have a rapid onset of action
B) The drug will be rapidly excreted by the kidneys
C) Only 5% of the drug is pharmacologically active
D) The drug has a high volume of distribution
Correct Answer: C) Only 5% of the drug is pharmacologically active
, Rationale: Only the unbound (free) fraction of a drug is
pharmacologically active and able to cross cell membranes. A drug
that is 95% protein-bound has only 5% free drug available for
therapeutic effect. This is clinically significant because changes in
protein binding (e.g., hypoalbuminemia, drug displacement) can
increase the free fraction and lead to toxicity. Option A (rapid onset) is
incorrect because protein binding delays drug distribution. Option B
(rapid excretion) is incorrect because protein-bound drugs are not
filtered by the kidneys. Option D (high volume of distribution) is
incorrect; low protein binding is associated with high Vd, not high
protein binding. Monitoring free drug levels may be necessary.
Question 5:
Which of the following factors would most likely decrease drug
absorption when administered orally?
A) Presence of food in the stomach
B) Increased gastric motility
C) Administration with a full glass of water
D) Acidic environment in the stomach
Correct Answer: B) Increased gastric motility
Rationale: Increased gastric motility decreases the time a drug spends
in the GI tract, reducing absorption. Options A (presence of food) can
either increase or decrease absorption depending on the drug (food
slows gastric emptying but may enhance absorption of lipophilic
drugs). Option C (water) generally enhances absorption by dissolving
the drug. Option D (acidic environment) can enhance absorption of
weak acids (e.g., aspirin). Understanding factors affecting drug
absorption is essential for medication administration and patient
education.
Final Practice Exam 100 Questions
with Correct Answers and Detailed
Rationales
INSTRUCTIONS:
This comprehensive practice exam covers key pharmacotherapeutic
concepts for nursing students. Each question includes the correct
answer and a detailed rationale explaining the underlying
pharmacology, nursing implications, and clinical decision-making. Use
this to prepare for your NSG 1540 final examination.
SECTION 1: Fundamental Pharmacology
Principles (Questions 1-15)
Question 1:
A nurse is preparing to administer a medication that has a half-life of 4
hours. After 24 hours, approximately what percentage of the drug
remains in the patient's body?
A) 50%
B) 25%
C) 6.25%
D) 1.56%
Correct Answer: D) 1.56%
,Rationale: After one half-life (4 hours), 50% remains. After 2 half-lives
(8 hours), 25% remains. After 3 half-lives (12 hours), 12.5% remains.
After 4 half-lives (16 hours), 6.25% remains. After 5 half-lives (20
hours), 3.125% remains. After 6 half-lives (24 hours), approximately
1.56% remains. This concept is critical for understanding drug
elimination, dosing intervals, and time to steady state (typically 4-5
half-lives). Nurses must understand half-life to monitor drug
accumulation and toxicity.
Question 2:
A patient with liver disease is prescribed a medication that undergoes
extensive first-pass metabolism. The nurse anticipates that the
prescriber may need to:
A) Increase the oral dose
B) Decrease the oral dose
C) Administer the medication by a different route to bypass first-pass
effect
D) Increase the frequency of administration
Correct Answer: C) Administer the medication by a different route to
bypass first-pass effect
Rationale: First-pass metabolism occurs when drugs are absorbed
from the GI tract and metabolized by the liver before reaching
systemic circulation. In liver disease, metabolism is impaired, leading
to higher bioavailability and potential toxicity. Administering the drug
via a route that bypasses the liver (e.g., sublingual, IV, transdermal)
avoids first-pass metabolism. Option A (increasing oral dose) would
worsen toxicity. Option B (decreasing oral dose) might be considered,
but route change is the most definitive. Option D (increasing
frequency) would also worsen toxicity. This is a key concept in
pharmacokinetics for patients with hepatic impairment.
,Question 3:
The nurse understands that the therapeutic index of a drug is a
measure of:
A) The drug's potency
B) The drug's efficacy
C) The drug's safety margin
D) The drug's absorption rate
Correct Answer: C) The drug's safety margin
Rationale: The therapeutic index (TI) is the ratio of the lethal dose
(LD50) to the effective dose (ED50) or the toxic dose (TD50) to the
effective dose. A high TI indicates a wide margin of safety (e.g.,
penicillin), while a low TI indicates a narrow margin (e.g., digoxin,
lithium, warfarin). Option A (potency) refers to the amount of drug
needed to produce an effect. Option B (efficacy) refers to the
maximum effect a drug can achieve. Option D (absorption) is a
pharmacokinetic property. Understanding TI helps nurses identify
drugs requiring close monitoring of serum levels and adverse effects.
Question 4:
A patient is receiving a drug that is 95% protein-bound. Which
statement best describes the clinical significance of this?
A) The drug will have a rapid onset of action
B) The drug will be rapidly excreted by the kidneys
C) Only 5% of the drug is pharmacologically active
D) The drug has a high volume of distribution
Correct Answer: C) Only 5% of the drug is pharmacologically active
, Rationale: Only the unbound (free) fraction of a drug is
pharmacologically active and able to cross cell membranes. A drug
that is 95% protein-bound has only 5% free drug available for
therapeutic effect. This is clinically significant because changes in
protein binding (e.g., hypoalbuminemia, drug displacement) can
increase the free fraction and lead to toxicity. Option A (rapid onset) is
incorrect because protein binding delays drug distribution. Option B
(rapid excretion) is incorrect because protein-bound drugs are not
filtered by the kidneys. Option D (high volume of distribution) is
incorrect; low protein binding is associated with high Vd, not high
protein binding. Monitoring free drug levels may be necessary.
Question 5:
Which of the following factors would most likely decrease drug
absorption when administered orally?
A) Presence of food in the stomach
B) Increased gastric motility
C) Administration with a full glass of water
D) Acidic environment in the stomach
Correct Answer: B) Increased gastric motility
Rationale: Increased gastric motility decreases the time a drug spends
in the GI tract, reducing absorption. Options A (presence of food) can
either increase or decrease absorption depending on the drug (food
slows gastric emptying but may enhance absorption of lipophilic
drugs). Option C (water) generally enhances absorption by dissolving
the drug. Option D (acidic environment) can enhance absorption of
weak acids (e.g., aspirin). Understanding factors affecting drug
absorption is essential for medication administration and patient
education.
