NR571 Final Examination with correct
answers and rationale updated 2026
1. A 72-year-old male with a history of atrial fibrillation and hypertension is started on warfarin.
Which pharmacokinetic parameter is most affected in geriatric patients, leading to a lower required
dose?
A. Increased renal clearance
B. Increased hepatic blood flow
C. " CORRECTANSWERDecreased first-pass metabolism</span>
D. Increased protein binding
Rationale: Age-related decreases in hepatic mass and blood flow reduce first-pass metabolism,
leading to higher bioavailability of drugs like warfarin. Renal clearance typically decreases, not
increases.
2. A patient is prescribed a drug that acts as an agonist at Beta-2 receptors. What is the primary
physiological effect?
A. Increased heart rate and contractility
B. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Bronchodilation and
vasodilation</span>
C. Vasoconstriction of peripheral vessels
D. Decreased gastrointestinal motility
Rationale: Beta-2 receptors are primarily found in the lungs (bronchial smooth muscle) and
peripheral vasculature. Stimulation leads to relaxation (bronchodilation & vasodilation). Beta-1 is
primarily cardiac.
3. Which of the following best describes the mechanism of action of ACE inhibitors?
A. Block the AT1 receptor site
B. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Prevent conversion of
Angiotensin I to Angiotensin II</span>
,C. Inhibit the reuptake of norepinephrine
D. Stimulate the release of renin
Rationale: ACE (Angiotensin-Converting Enzyme) inhibitors specifically block the enzyme responsible
for converting Angiotensin I to the potent vasoconstrictor Angiotensin II.
4. A patient on Lisinopril develops a dry, hacking cough. What is the most likely pathophysiological
mechanism?
A. Bronchospasm caused by Beta blockade
B. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Accumulation of bradykinin in the
lungs</span>
C. Direct irritation of the vagus nerve
D. Histamine release from mast cells
Rationale: ACE is also responsible for breaking down bradykinin. Inhibition of ACE leads to bradykinin
accumulation, which irritates the airways and causes a cough.
5. A patient is prescribed Metformin. What is the most significant adverse effect the nurse must
monitor for?
A. Hypoglycemia
B. <span style=" CORRECTANSWER:: -weight: bold
C. Weight gain
D. Stevens-Johnson Syndrome
Rationale: Lactic acidosis is a rare but serious adverse effect of Metformin, particularly in patients
with renal impairment, liver disease, or alcohol abuse.
6. Which class of antiarrhythmic drugs works primarily by blocking sodium channels and slowing
phase 0 depolarization?
A. Class II (Beta Blockers)
B. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Class I (e.g., Lidocaine,
Procainamide)</span>
C. Class III (e.g., Amiodarone)
D. Class IV (Calcium Channel Blockers)
,Rationale: Class I antiarrhythmics are membrane stabilizers that block fast sodium channels. Class III
blocks potassium channels, Class II blocks beta-receptors, and Class IV blocks calcium channels.
7. A patient on Digoxin has a serum potassium level of 2.8 mEq/L. What is the primary risk?
A. Decreased digoxin efficacy
B. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Increased risk of digoxin
toxicity</span>
C. Increased heart rate
D. Hypersensitivity reaction
Rationale: Hypokalemia reduces the binding of potassium to the Na+/K+ ATPase pump, allowing
digoxin to bind more readily, leading to enhanced toxicity (dysrhythmias).
8. Which opioid antagonist is used specifically to reverse opioid-induced constipation without
reversing analgesia?
A. Naloxone
B. Naltrexone
C. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Methylnaltrexone</span>
D. Flumazenil
Rationale: Methylnaltrexone is a peripheral mu-opioid receptor antagonist. It does not cross the
blood-brain barrier, so it blocks constipation in the gut without affecting central pain relief.
9. A patient is being treated for tuberculosis with a four-drug regimen. Which drug is associated with
optic neuritis and requires baseline eye exams?
A. Isoniazid
B. Rifampin
C. Pyrazinamide
D. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Ethambutol</span>
Rationale: Ethambutol is known for causing dose-dependent optic neuritis (blurred vision, red-green
CORRECTANSWER: blindness). It requires baseline and monthly visual acuity testing.
, 10. What is the primary mechanism of action of SSRIs (Selective Serotonin Reuptake Inhibitors)?
A. Inhibition of MAO-A and MAO-B
B. Blockade of D2 receptors
C. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Inhibition of serotonin reuptake
into the presynaptic neuron</span>
D. Antagonism of alpha-1 receptors
Rationale: SSRIs block the serotonin transporter (SERT) on the presynaptic membrane, increasing the
concentration of serotonin in the synaptic cleft.
11. A patient on SSRI therapy is prescribed Linezolid for a skin infection. What is the primary
concern?
A. Decreased antibiotic efficacy
B. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Serotonin Syndrome</span>
C. Hypertensive crisis
D. QT prolongation
Rationale: Linezolid has weak MAO-inhibiting properties. Combining it with an SSRI increases the risk
of Serotonin Syndrome (agitation, hyperthermia, clonus).
12. Which anti-epileptic drug is the first-line for trigeminal neuralgia?
A. Phenytoin
B. Valproic Acid
C. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Carbamazepine</span>
D. Levetiracetam
Rationale: Carbamazepine is the drug of choice for trigeminal neuralgia due to its ability to stabilize
neuronal membranes in the trigeminal nerve.
13. A patient is started on Vancomycin. The nurse notes a "red man syndrome" during the infusion.
What is the best immediate action?
answers and rationale updated 2026
1. A 72-year-old male with a history of atrial fibrillation and hypertension is started on warfarin.
Which pharmacokinetic parameter is most affected in geriatric patients, leading to a lower required
dose?
A. Increased renal clearance
B. Increased hepatic blood flow
C. " CORRECTANSWERDecreased first-pass metabolism</span>
D. Increased protein binding
Rationale: Age-related decreases in hepatic mass and blood flow reduce first-pass metabolism,
leading to higher bioavailability of drugs like warfarin. Renal clearance typically decreases, not
increases.
2. A patient is prescribed a drug that acts as an agonist at Beta-2 receptors. What is the primary
physiological effect?
A. Increased heart rate and contractility
B. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Bronchodilation and
vasodilation</span>
C. Vasoconstriction of peripheral vessels
D. Decreased gastrointestinal motility
Rationale: Beta-2 receptors are primarily found in the lungs (bronchial smooth muscle) and
peripheral vasculature. Stimulation leads to relaxation (bronchodilation & vasodilation). Beta-1 is
primarily cardiac.
3. Which of the following best describes the mechanism of action of ACE inhibitors?
A. Block the AT1 receptor site
B. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Prevent conversion of
Angiotensin I to Angiotensin II</span>
,C. Inhibit the reuptake of norepinephrine
D. Stimulate the release of renin
Rationale: ACE (Angiotensin-Converting Enzyme) inhibitors specifically block the enzyme responsible
for converting Angiotensin I to the potent vasoconstrictor Angiotensin II.
4. A patient on Lisinopril develops a dry, hacking cough. What is the most likely pathophysiological
mechanism?
A. Bronchospasm caused by Beta blockade
B. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Accumulation of bradykinin in the
lungs</span>
C. Direct irritation of the vagus nerve
D. Histamine release from mast cells
Rationale: ACE is also responsible for breaking down bradykinin. Inhibition of ACE leads to bradykinin
accumulation, which irritates the airways and causes a cough.
5. A patient is prescribed Metformin. What is the most significant adverse effect the nurse must
monitor for?
A. Hypoglycemia
B. <span style=" CORRECTANSWER:: -weight: bold
C. Weight gain
D. Stevens-Johnson Syndrome
Rationale: Lactic acidosis is a rare but serious adverse effect of Metformin, particularly in patients
with renal impairment, liver disease, or alcohol abuse.
6. Which class of antiarrhythmic drugs works primarily by blocking sodium channels and slowing
phase 0 depolarization?
A. Class II (Beta Blockers)
B. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Class I (e.g., Lidocaine,
Procainamide)</span>
C. Class III (e.g., Amiodarone)
D. Class IV (Calcium Channel Blockers)
,Rationale: Class I antiarrhythmics are membrane stabilizers that block fast sodium channels. Class III
blocks potassium channels, Class II blocks beta-receptors, and Class IV blocks calcium channels.
7. A patient on Digoxin has a serum potassium level of 2.8 mEq/L. What is the primary risk?
A. Decreased digoxin efficacy
B. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Increased risk of digoxin
toxicity</span>
C. Increased heart rate
D. Hypersensitivity reaction
Rationale: Hypokalemia reduces the binding of potassium to the Na+/K+ ATPase pump, allowing
digoxin to bind more readily, leading to enhanced toxicity (dysrhythmias).
8. Which opioid antagonist is used specifically to reverse opioid-induced constipation without
reversing analgesia?
A. Naloxone
B. Naltrexone
C. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Methylnaltrexone</span>
D. Flumazenil
Rationale: Methylnaltrexone is a peripheral mu-opioid receptor antagonist. It does not cross the
blood-brain barrier, so it blocks constipation in the gut without affecting central pain relief.
9. A patient is being treated for tuberculosis with a four-drug regimen. Which drug is associated with
optic neuritis and requires baseline eye exams?
A. Isoniazid
B. Rifampin
C. Pyrazinamide
D. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Ethambutol</span>
Rationale: Ethambutol is known for causing dose-dependent optic neuritis (blurred vision, red-green
CORRECTANSWER: blindness). It requires baseline and monthly visual acuity testing.
, 10. What is the primary mechanism of action of SSRIs (Selective Serotonin Reuptake Inhibitors)?
A. Inhibition of MAO-A and MAO-B
B. Blockade of D2 receptors
C. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Inhibition of serotonin reuptake
into the presynaptic neuron</span>
D. Antagonism of alpha-1 receptors
Rationale: SSRIs block the serotonin transporter (SERT) on the presynaptic membrane, increasing the
concentration of serotonin in the synaptic cleft.
11. A patient on SSRI therapy is prescribed Linezolid for a skin infection. What is the primary
concern?
A. Decreased antibiotic efficacy
B. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Serotonin Syndrome</span>
C. Hypertensive crisis
D. QT prolongation
Rationale: Linezolid has weak MAO-inhibiting properties. Combining it with an SSRI increases the risk
of Serotonin Syndrome (agitation, hyperthermia, clonus).
12. Which anti-epileptic drug is the first-line for trigeminal neuralgia?
A. Phenytoin
B. Valproic Acid
C. <span style=" CORRECTANSWER:: #2E8B57; font-weight: bold;">Carbamazepine</span>
D. Levetiracetam
Rationale: Carbamazepine is the drug of choice for trigeminal neuralgia due to its ability to stabilize
neuronal membranes in the trigeminal nerve.
13. A patient is started on Vancomycin. The nurse notes a "red man syndrome" during the infusion.
What is the best immediate action?
