NCLEX RN Pharmacology Practice Questions
And Answers Detailed Rationales
Verified Tests
Question 1 [Cardiovascular / Anticoagulants]
A client with atrial fibrillation is prescribed warfarin (Coumadin) 5 mg PO daily. The
nurse reviews the client's laboratory results and notes an INR of 4.2. Which action
should the nurse take first?
1. A. Administer the scheduled dose of warfarin.
2. B. Hold the warfarin and notify the healthcare provider.
3. C. Administer vitamin K subcutaneously.
4. D. Draw a STAT PT/INR level.
Correct Answer: B
Rationale: The therapeutic INR range for atrial fibrillation is typically 2.0–3.0. An INR of 4.2
indicates the client is at increased risk for bleeding. The nurse's first action is to hold the
warfarin dose and notify the provider. While vitamin K is the antidote for warfarin toxicity,
it requires a provider's order. Administering the dose (A) would worsen the risk. Drawing
another INR (D) is unnecessary when the result is already significantly elevated.
Question 2 [Cardiovascular / Cardiac Glycosides]
A client receiving digoxin (Lanoxin) 0.25 mg daily reports nausea and visual
disturbances. The nurse checks the apical pulse and finds it to be 52 beats/min. What
is the nurse's priority action?
5. A. Continue to monitor the client's vital signs.
6. B. Administer the digoxin as scheduled.
7. C. Hold the digoxin and notify the healthcare provider.
8. D. Check the client's potassium level.
Correct Answer: C
Rationale: Digoxin toxicity is characterized by nausea, vomiting, visual disturbances
(yellow-green halos), and bradycardia (heart rate <60 bpm). The nurse must hold the
digoxin and notify the provider immediately. While checking potassium (D) is relevant
(hypokalemia increases digoxin toxicity), the immediate priority is to stop administration to
prevent further toxicity. Continuing to monitor (A) or administering the dose (B) would be
unsafe.
,Question 3 [Cardiovascular / Anticoagulants]
The nurse is teaching a client about home administration of subcutaneous
enoxaparin (Lovenox). Which statement by the client indicates correct
understanding?
9. A. I should massage the injection site after administering the medication.
10. B. I will inject the medication into my thigh muscle.
11. C. I should expel the air bubble before injecting.
12. D. I will inject into my abdomen at least 2 inches from my belly button.
Correct Answer: D
Rationale: Enoxaparin is administered subcutaneously into the abdomen, at least 2 inches
away from the umbilicus. The client should NOT massage the site (A) as this can cause
bruising and hematoma. It is NOT given IM (B). The prefilled syringe contains an air bubble
that should NOT be expelled (C) — the bubble pushes the medication out of the needle and
ensures the full dose is delivered.
Question 4 [Cardiovascular / Diuretics]
A client with heart failure is prescribed furosemide (Lasix) 40 mg IV. The nurse
should monitor the client for which adverse effect?
13. A. Hyperkalemia
14. B. Hypokalemia
15. C. Hypernatremia
16. D. Hypercalcemia
Correct Answer: B
Rationale: Furosemide is a loop diuretic that acts on the ascending loop of Henle, causing
increased excretion of sodium, chloride, water, potassium, calcium, and magnesium. The
most significant adverse effect is hypokalemia, which can lead to life-threatening cardiac
dysrhythmias. The nurse should monitor potassium levels and assess for signs such as
muscle weakness, fatigue, and irregular pulse.
Question 5 [Cardiovascular / Antihypertensives]
The nurse is preparing to administer metoprolol (Lopressor) 50 mg PO to a client
with hypertension. Before giving the medication, the nurse should assess:
, 17. A. Respiratory rate
18. B. Blood pressure and apical pulse
19. C. Serum creatinine
20. D. Liver function tests
Correct Answer: B
Rationale: Metoprolol is a beta-1 selective blocker that decreases heart rate, myocardial
contractility, and blood pressure. The nurse must assess blood pressure and apical pulse
before administration. If the systolic BP is <90 mmHg or the heart rate is <60 bpm, the
medication should be held and the provider notified. While renal and hepatic function are
important baseline assessments, they are not required immediately before each dose.
Question 6 [Cardiovascular / Antianginals]
A client with angina is prescribed nitroglycerin sublingual tablets. The nurse should
instruct the client to take the medication when chest pain occurs and to:
21. A. Swallow the tablet with a full glass of water.
22. B. Place the tablet under the tongue and let it dissolve.
23. C. Chew the tablet thoroughly before swallowing.
24. D. Take the tablet with food to prevent stomach upset.
Correct Answer: B
Rationale: Nitroglycerin is administered sublingually (under the tongue) for rapid
absorption through the rich vascular network in the oral mucosa. Swallowing the tablet (A)
would result in first-pass hepatic metabolism, significantly reducing bioavailability.
Chewing (C) is incorrect. Food is not required (D). The client should sit down before taking
the medication to prevent orthostatic hypotension and dizziness.
Question 7 [Cardiovascular / Anticoagulants]
A client is receiving heparin IV infusion. The healthcare provider orders protamine
sulfate. The nurse understands that protamine sulfate is the antidote for heparin
because it:
25. A. Enhances the metabolism of heparin in the liver.
26. B. Forms a stable salt with heparin, neutralizing its anticoagulant effects.
27. C. Increases platelet production to counteract bleeding.
28. D. Activates vitamin K-dependent clotting factors.
Correct Answer: B
And Answers Detailed Rationales
Verified Tests
Question 1 [Cardiovascular / Anticoagulants]
A client with atrial fibrillation is prescribed warfarin (Coumadin) 5 mg PO daily. The
nurse reviews the client's laboratory results and notes an INR of 4.2. Which action
should the nurse take first?
1. A. Administer the scheduled dose of warfarin.
2. B. Hold the warfarin and notify the healthcare provider.
3. C. Administer vitamin K subcutaneously.
4. D. Draw a STAT PT/INR level.
Correct Answer: B
Rationale: The therapeutic INR range for atrial fibrillation is typically 2.0–3.0. An INR of 4.2
indicates the client is at increased risk for bleeding. The nurse's first action is to hold the
warfarin dose and notify the provider. While vitamin K is the antidote for warfarin toxicity,
it requires a provider's order. Administering the dose (A) would worsen the risk. Drawing
another INR (D) is unnecessary when the result is already significantly elevated.
Question 2 [Cardiovascular / Cardiac Glycosides]
A client receiving digoxin (Lanoxin) 0.25 mg daily reports nausea and visual
disturbances. The nurse checks the apical pulse and finds it to be 52 beats/min. What
is the nurse's priority action?
5. A. Continue to monitor the client's vital signs.
6. B. Administer the digoxin as scheduled.
7. C. Hold the digoxin and notify the healthcare provider.
8. D. Check the client's potassium level.
Correct Answer: C
Rationale: Digoxin toxicity is characterized by nausea, vomiting, visual disturbances
(yellow-green halos), and bradycardia (heart rate <60 bpm). The nurse must hold the
digoxin and notify the provider immediately. While checking potassium (D) is relevant
(hypokalemia increases digoxin toxicity), the immediate priority is to stop administration to
prevent further toxicity. Continuing to monitor (A) or administering the dose (B) would be
unsafe.
,Question 3 [Cardiovascular / Anticoagulants]
The nurse is teaching a client about home administration of subcutaneous
enoxaparin (Lovenox). Which statement by the client indicates correct
understanding?
9. A. I should massage the injection site after administering the medication.
10. B. I will inject the medication into my thigh muscle.
11. C. I should expel the air bubble before injecting.
12. D. I will inject into my abdomen at least 2 inches from my belly button.
Correct Answer: D
Rationale: Enoxaparin is administered subcutaneously into the abdomen, at least 2 inches
away from the umbilicus. The client should NOT massage the site (A) as this can cause
bruising and hematoma. It is NOT given IM (B). The prefilled syringe contains an air bubble
that should NOT be expelled (C) — the bubble pushes the medication out of the needle and
ensures the full dose is delivered.
Question 4 [Cardiovascular / Diuretics]
A client with heart failure is prescribed furosemide (Lasix) 40 mg IV. The nurse
should monitor the client for which adverse effect?
13. A. Hyperkalemia
14. B. Hypokalemia
15. C. Hypernatremia
16. D. Hypercalcemia
Correct Answer: B
Rationale: Furosemide is a loop diuretic that acts on the ascending loop of Henle, causing
increased excretion of sodium, chloride, water, potassium, calcium, and magnesium. The
most significant adverse effect is hypokalemia, which can lead to life-threatening cardiac
dysrhythmias. The nurse should monitor potassium levels and assess for signs such as
muscle weakness, fatigue, and irregular pulse.
Question 5 [Cardiovascular / Antihypertensives]
The nurse is preparing to administer metoprolol (Lopressor) 50 mg PO to a client
with hypertension. Before giving the medication, the nurse should assess:
, 17. A. Respiratory rate
18. B. Blood pressure and apical pulse
19. C. Serum creatinine
20. D. Liver function tests
Correct Answer: B
Rationale: Metoprolol is a beta-1 selective blocker that decreases heart rate, myocardial
contractility, and blood pressure. The nurse must assess blood pressure and apical pulse
before administration. If the systolic BP is <90 mmHg or the heart rate is <60 bpm, the
medication should be held and the provider notified. While renal and hepatic function are
important baseline assessments, they are not required immediately before each dose.
Question 6 [Cardiovascular / Antianginals]
A client with angina is prescribed nitroglycerin sublingual tablets. The nurse should
instruct the client to take the medication when chest pain occurs and to:
21. A. Swallow the tablet with a full glass of water.
22. B. Place the tablet under the tongue and let it dissolve.
23. C. Chew the tablet thoroughly before swallowing.
24. D. Take the tablet with food to prevent stomach upset.
Correct Answer: B
Rationale: Nitroglycerin is administered sublingually (under the tongue) for rapid
absorption through the rich vascular network in the oral mucosa. Swallowing the tablet (A)
would result in first-pass hepatic metabolism, significantly reducing bioavailability.
Chewing (C) is incorrect. Food is not required (D). The client should sit down before taking
the medication to prevent orthostatic hypotension and dizziness.
Question 7 [Cardiovascular / Anticoagulants]
A client is receiving heparin IV infusion. The healthcare provider orders protamine
sulfate. The nurse understands that protamine sulfate is the antidote for heparin
because it:
25. A. Enhances the metabolism of heparin in the liver.
26. B. Forms a stable salt with heparin, neutralizing its anticoagulant effects.
27. C. Increases platelet production to counteract bleeding.
28. D. Activates vitamin K-dependent clotting factors.
Correct Answer: B
