PHARMACOLOGY NURSING REVIEW MODULE 3
COMPREHENSIVE EXAMINATION | MEDICATION
ADMINISTRATION, DRUG CLASSIFICATIONS &
MEDICATION SAFETY | NCLEX RN PHARMACOLOGY
STUDY GUIDE & EXAM QUESTIONS
SECTION A: PHARMACOKINETICS AND PHARMACODYNAMICS
Questions 1-25
1. A patient with severe liver disease is prescribed a medication that undergoes extensive
first-pass metabolism. The nurse anticipates that the prescriber will:
A. Increase the oral dose to achieve therapeutic effect
B. Administer the medication via the intravenous route
C. Decrease the oral dose to prevent toxicity
D. Administer the medication via the subcutaneous route
Answer: B. Administer the medication via the intravenous route
Rationale: First-pass metabolism occurs in the liver where oral drugs are metabolized
before reaching systemic circulation. In liver disease, this metabolism is impaired, but IV
administration bypasses first-pass effect entirely, providing more predictable drug levels.
,2. A nurse is calculating the half-life of a medication. The medication has a half-life of 4
hours. What percentage of the drug remains in the body after 16 hours?
A. 25%
B. 12.5%
C. 6.25%
D. 3.125%
Answer: C. 6.25%
Rationale: After each half-life, 50% of the drug remains. After 4 half-lives (16 hours): 100% →
50% → 25% → 12.5% → 6.25%. The formula is (0.5)^n where n is the number of half-lives.
3. A patient's serum drug level is measured at 15 mcg/mL, and the therapeutic range is 10-
20 mcg/mL. The drug has a half-life of 6 hours. When should the nurse anticipate the next
trough level should be drawn?
A. Immediately before the next scheduled dose
B. 30 minutes after the dose is administered
C. 2 hours after the dose is administered
D. 6 hours after the dose is administered
Answer: A. Immediately before the next scheduled dose
Rationale: Trough levels represent the lowest concentration of drug in the patient's
bloodstream and should be drawn immediately before the next dose is administered to
assess for potential toxicity and determine dosing intervals.
4. Which of the following factors would MOST significantly increase the volume of
distribution of a lipophilic drug?
A. Increased plasma protein binding
B. Decreased adipose tissue
C. Increased adipose tissue
D. Decreased cardiac output
Answer: C. Increased adipose tissue
Rationale: Lipophilic drugs distribute extensively into adipose tissue. Increased body fat
provides more storage sites, increasing the volume of distribution. This can prolong the
drug's elimination half-life as it slowly releases from fat stores.
,5. A patient is receiving a medication that is 95% protein-bound. Which laboratory value is
MOST important to monitor?
A. Serum creatinine
B. Serum albumin
C. White blood cell count
D. Serum sodium
Answer: B. Serum albumin
Rationale: Highly protein-bound drugs (≥90%) are primarily bound to albumin. Low albumin
levels (hypoalbuminemia) increase the free, active drug concentration, potentially leading
to toxicity. Monitoring albumin is essential for dose adjustment.
6. The nurse understands that the blood-brain barrier (BBB) allows passage of drugs that
are:
A. Highly polar and water-soluble
B. Lipid-soluble and non-ionized
C. Highly ionized and protein-bound
D. Large molecular weight compounds
Answer: B. Lipid-soluble and non-ionized
Rationale: The BBB is composed of tight junctions between endothelial cells. Lipid-soluble,
non-ionized drugs can cross the BBB more easily, while polar, water-soluble, and ionized
drugs have limited penetration.
7. A patient is started on a new medication. The nurse notes that the drug has a narrow
therapeutic index. This means that:
A. The drug has a wide margin of safety
B. The drug has a high potential for toxicity
C. The drug is safe at any dose
D. The drug requires no monitoring
Answer: B. The drug has a high potential for toxicity
Rationale: A narrow therapeutic index means there is a small difference between the
therapeutic dose and the toxic dose. These drugs require careful monitoring of serum levels
to maintain efficacy while avoiding toxicity (e.g., digoxin, warfarin, lithium).
, 8. Which route of medication administration has the FASTEST onset of action?
A. Sublingual
B. Oral
C. Intramuscular
D. Intravenous
Answer: D. Intravenous
Rationale: IV administration delivers the drug directly into the bloodstream, achieving 100%
bioavailability and the fastest onset of action. Sublingual administration provides rapid
onset but is slower than IV. Oral administration has the slowest onset due to absorption
and first-pass metabolism.
9. The nurse is teaching a patient about enteric-coated tablets. The patient should be
instructed to:
A. Crush the tablet for easier swallowing
B. Chew the tablet thoroughly
C. Swallow the tablet whole
D. Dissolve the tablet in water
Answer: C. Swallow the tablet whole
Rationale: Enteric-coated tablets are designed to dissolve in the small intestine rather than
the stomach. Crushing, chewing, or dissolving destroys the protective coating, causing the
drug to be released in the stomach where it may be destroyed by gastric acid or cause
irritation.
10. A medication with a half-life of 24 hours is administered once daily. How many days will
it take to reach steady state?
A. 2 days
B. 3 days
C. 4-5 days
D. 7 days
Answer: C. 4-5 days
Rationale: Steady state is achieved after approximately 4-5 half-lives. With a half-life of 24
hours, steady state would be reached in approximately 4-5 days. At steady state, drug
accumulation and elimination are balanced.
COMPREHENSIVE EXAMINATION | MEDICATION
ADMINISTRATION, DRUG CLASSIFICATIONS &
MEDICATION SAFETY | NCLEX RN PHARMACOLOGY
STUDY GUIDE & EXAM QUESTIONS
SECTION A: PHARMACOKINETICS AND PHARMACODYNAMICS
Questions 1-25
1. A patient with severe liver disease is prescribed a medication that undergoes extensive
first-pass metabolism. The nurse anticipates that the prescriber will:
A. Increase the oral dose to achieve therapeutic effect
B. Administer the medication via the intravenous route
C. Decrease the oral dose to prevent toxicity
D. Administer the medication via the subcutaneous route
Answer: B. Administer the medication via the intravenous route
Rationale: First-pass metabolism occurs in the liver where oral drugs are metabolized
before reaching systemic circulation. In liver disease, this metabolism is impaired, but IV
administration bypasses first-pass effect entirely, providing more predictable drug levels.
,2. A nurse is calculating the half-life of a medication. The medication has a half-life of 4
hours. What percentage of the drug remains in the body after 16 hours?
A. 25%
B. 12.5%
C. 6.25%
D. 3.125%
Answer: C. 6.25%
Rationale: After each half-life, 50% of the drug remains. After 4 half-lives (16 hours): 100% →
50% → 25% → 12.5% → 6.25%. The formula is (0.5)^n where n is the number of half-lives.
3. A patient's serum drug level is measured at 15 mcg/mL, and the therapeutic range is 10-
20 mcg/mL. The drug has a half-life of 6 hours. When should the nurse anticipate the next
trough level should be drawn?
A. Immediately before the next scheduled dose
B. 30 minutes after the dose is administered
C. 2 hours after the dose is administered
D. 6 hours after the dose is administered
Answer: A. Immediately before the next scheduled dose
Rationale: Trough levels represent the lowest concentration of drug in the patient's
bloodstream and should be drawn immediately before the next dose is administered to
assess for potential toxicity and determine dosing intervals.
4. Which of the following factors would MOST significantly increase the volume of
distribution of a lipophilic drug?
A. Increased plasma protein binding
B. Decreased adipose tissue
C. Increased adipose tissue
D. Decreased cardiac output
Answer: C. Increased adipose tissue
Rationale: Lipophilic drugs distribute extensively into adipose tissue. Increased body fat
provides more storage sites, increasing the volume of distribution. This can prolong the
drug's elimination half-life as it slowly releases from fat stores.
,5. A patient is receiving a medication that is 95% protein-bound. Which laboratory value is
MOST important to monitor?
A. Serum creatinine
B. Serum albumin
C. White blood cell count
D. Serum sodium
Answer: B. Serum albumin
Rationale: Highly protein-bound drugs (≥90%) are primarily bound to albumin. Low albumin
levels (hypoalbuminemia) increase the free, active drug concentration, potentially leading
to toxicity. Monitoring albumin is essential for dose adjustment.
6. The nurse understands that the blood-brain barrier (BBB) allows passage of drugs that
are:
A. Highly polar and water-soluble
B. Lipid-soluble and non-ionized
C. Highly ionized and protein-bound
D. Large molecular weight compounds
Answer: B. Lipid-soluble and non-ionized
Rationale: The BBB is composed of tight junctions between endothelial cells. Lipid-soluble,
non-ionized drugs can cross the BBB more easily, while polar, water-soluble, and ionized
drugs have limited penetration.
7. A patient is started on a new medication. The nurse notes that the drug has a narrow
therapeutic index. This means that:
A. The drug has a wide margin of safety
B. The drug has a high potential for toxicity
C. The drug is safe at any dose
D. The drug requires no monitoring
Answer: B. The drug has a high potential for toxicity
Rationale: A narrow therapeutic index means there is a small difference between the
therapeutic dose and the toxic dose. These drugs require careful monitoring of serum levels
to maintain efficacy while avoiding toxicity (e.g., digoxin, warfarin, lithium).
, 8. Which route of medication administration has the FASTEST onset of action?
A. Sublingual
B. Oral
C. Intramuscular
D. Intravenous
Answer: D. Intravenous
Rationale: IV administration delivers the drug directly into the bloodstream, achieving 100%
bioavailability and the fastest onset of action. Sublingual administration provides rapid
onset but is slower than IV. Oral administration has the slowest onset due to absorption
and first-pass metabolism.
9. The nurse is teaching a patient about enteric-coated tablets. The patient should be
instructed to:
A. Crush the tablet for easier swallowing
B. Chew the tablet thoroughly
C. Swallow the tablet whole
D. Dissolve the tablet in water
Answer: C. Swallow the tablet whole
Rationale: Enteric-coated tablets are designed to dissolve in the small intestine rather than
the stomach. Crushing, chewing, or dissolving destroys the protective coating, causing the
drug to be released in the stomach where it may be destroyed by gastric acid or cause
irritation.
10. A medication with a half-life of 24 hours is administered once daily. How many days will
it take to reach steady state?
A. 2 days
B. 3 days
C. 4-5 days
D. 7 days
Answer: C. 4-5 days
Rationale: Steady state is achieved after approximately 4-5 half-lives. With a half-life of 24
hours, steady state would be reached in approximately 4-5 days. At steady state, drug
accumulation and elimination are balanced.
