Introduction
Pharmacological therapies represent one of the most critical and frequently tested areas in LPN/LVN examinations, accounting for 10-16% of the NCLEX-PN exam content. This topic area encompasses the essential knowledge and skills required for safe medication administration, a fundamental responsibility of licensed practical nurses. Understanding pharmacological principles is not merely academic—it directly impacts patient safety and outcomes in clinical practice. LPNs must demonstrate competency in medication calculation, administration techniques, recognition of therapeutic effects, identification of adverse reactions, and understanding of drug interactions. The complexity of modern healthcare requires nurses to be knowledgeable about a wide range of medications, from basic analgesics to complex cardiovascular drugs. Patient safety depends on the nurse’s ability to perform accurate dosage calculations, understand the “five rights” of medication administration, and recognize when to hold or question medication orders. This knowledge extends beyond simple memorization to include understanding of pharmacokinetics, therapeutic ranges, and the physiological effects of medications on different body systems. Mastery of pharmacological therapies also involves patient education, ensuring clients understand their medications, potential side effects, and the importance of compliance. The questions in this practice set are designed to test these critical competencies and help you develop the clinical reasoning skills essential for safe nursing practice.
Practice Questions
Question 1:
A patient is prescribed digoxin 0.125 mg PO daily. The available tablets are 0.25 mg. How many tablets should the nurse administer?
A) 2 tablets
B) 1 tablet
C) 0.5 tablets
D) 1.5 tablets
Correct Answer: C) 0.5 tablets
Explanation: Using the dosage calculation formula: Desired dose (0.125 mg) ÷ Available dose (0.25 mg) = 0.5 tablets. This is a basic but critical calculation skill that prevents medication errors.
Question 2:
Which of the following is the most important assessment before administering digoxin?
A) Blood pressure
B) Respiratory rate
C) Apical pulse rate
D) Temperature
Correct Answer: C) Apical pulse rate
Explanation: Digoxin is a cardiac glycoside that can cause bradycardia and heart block. The apical pulse must be assessed for one full minute before administration, and digoxin should be held if the pulse is below 60 bpm in adults.
Question 3:
A patient receiving warfarin therapy should avoid which of the following foods?
A) Citrus fruits
B) Green leafy vegetables
C) Dairy products
D) Whole grains
Correct Answer: B) Green leafy vegetables
Explanation: Green leafy vegetables are high in vitamin K, which can interfere with warfarin’s anticoagulant effects. Patients should maintain consistent vitamin K intake rather than avoiding these foods completely.
Question 4:
The nurse is preparing to administer insulin. Which action demonstrates proper insulin administration technique?
A) Shaking the vial vigorously before drawing up the medication
B) Administering the injection at a 45-degree angle
C) Rotating injection sites to prevent lipodystrophy
D) Massaging the injection site after administration
Correct Answer: C) Rotating injection sites to prevent lipodystrophy
Explanation: Site rotation prevents lipodystrophy (tissue changes) and ensures consistent absorption. Insulin should not be shaken vigorously, the angle depends on needle length and body habitus, and massage can increase absorption rate unpredictably.
Question 5:
A patient is taking furosemide (Lasix). Which laboratory value should the nurse monitor most closely?
A) Blood glucose
B) Potassium level
C) White blood cell count
D) Hemoglobin
Correct Answer: B) Potassium level
Explanation: Furosemide is a loop diuretic that causes potassium loss through the kidneys. Hypokalemia can lead to dangerous cardiac arrhythmias, making potassium monitoring essential.
Question 6:
Which of the following medications requires the nurse to assess liver function before administration?
A) Acetaminophen (long-term use)
B) Ibuprofen
C) Aspirin
D) Morphine
Correct Answer: A) Acetaminophen (long-term use)
Explanation: Acetaminophen is metabolized by the liver and can cause hepatotoxicity, especially with prolonged use or overdose. Liver function tests should be monitored in patients on long-term therapy.
Question 7:
A patient is prescribed nitroglycerin sublingual tablets for chest pain. The nurse should instruct the patient to:
A) Take three tablets at once for severe pain
B) Take one tablet, wait 5 minutes, and call 911 if pain persists
C) Store tablets in the refrigerator
D) Chew the tablet for faster absorption
Correct Answer: B) Take one tablet, wait 5 minutes, and call 911 if pain persists
Explanation: The correct protocol is to take one tablet sublingually, wait 5 minutes for relief. If no relief, take a second tablet and call for emergency medical services. A third tablet may be taken after another 5 minutes if EMS has not arrived.
Question 8:
Which side effect is most commonly associated with ACE inhibitors?
A) Hyperkalemia
B) Dry cough
C) Weight gain
D) Diarrhea
Correct Answer: B) Dry cough
Explanation: A persistent, dry cough occurs in about 10-15% of patients taking ACE inhibitors due to increased bradykinin levels. This side effect typically resolves when the medication is discontinued.
Question 9:
A patient is receiving heparin therapy. Which laboratory test should be monitored to evaluate effectiveness?
A) PT/INR
B) aPTT
C) Platelet count
D) Hemoglobin
Correct Answer: B) aPTT
Explanation: Activated partial thromboplastin time (aPTT) is used to monitor heparin therapy effectiveness. The therapeutic range is typically 1.5-2.5 times the control value.
Question 10:
When administering medications through a nasogastric tube, the nurse should:
A) Mix all medications together for efficiency
B) Flush the tube with 30 mL of water between each medication
C) Use hot water to dissolve tablets faster
D) Administer medications without diluting them
Correct Answer: B) Flush the tube with 30 mL of water between each medication
Explanation: Flushing between medications prevents drug interactions and tube clogging. Each medication should be given separately with appropriate flushing before, between, and after administration.
Question 11:
Which instruction should the nurse give to a patient taking antibiotics?
A) Stop taking the medication when symptoms improve
B) Take the full course as prescribed, even if feeling better
C) Take with antacids to prevent stomach upset
D) Double the dose if a dose is missed
Correct Answer: B) Take the full course as prescribed, even if feeling better
Explanation: Completing the full antibiotic course prevents bacterial resistance and ensures complete elimination of the infection, even if symptoms resolve before the medication is finished.
Question 12:
A patient is prescribed prednisone. Which side effect should the nurse monitor for with long-term use?
A) Hypotension
B) Weight loss
C) Hyperglycemia
D) Bradycardia
Correct Answer: C) Hyperglycemia
Explanation: Corticosteroids like prednisone can cause hyperglycemia by promoting gluconeogenesis and reducing glucose uptake by tissues. Blood glucose should be monitored, especially in diabetic patients.
Question 13:
The nurse is teaching a patient about taking iron supplements. Which instruction is most important?
A) Take with milk for better absorption
B) Take on an empty stomach with orange juice
C) Take with meals to prevent constipation
D) Take at bedtime to avoid side effects
Correct Answer: B) Take on an empty stomach with orange juice
Explanation: Iron is best absorbed on an empty stomach, and vitamin C (in orange juice) enhances iron absorption. Taking with food or milk can decrease absorption significantly.
Question 14:
Which assessment finding indicates a therapeutic response to bronchodilator therapy?
A) Decreased heart rate
B) Improved breath sounds and easier breathing
C) Reduced blood pressure
D) Increased urination
Correct Answer: B) Improved breath sounds and easier breathing
Explanation: Bronchodilators work by relaxing smooth muscle in the airways, leading to bronchodilation. Therapeutic effects include improved breath sounds, reduced wheezing, and easier breathing.
Question 15:
A patient is taking lithium for bipolar disorder. Which instruction is most important for the nurse to provide?
A) Increase sodium intake significantly
B) Maintain consistent fluid intake and avoid dehydration
C) Take the medication only when feeling manic
D) Avoid all physical activity
Correct Answer: B) Maintain consistent fluid intake and avoid dehydration
Explanation: Lithium has a narrow therapeutic range, and blood levels can become toxic with dehydration. Consistent fluid intake and regular monitoring of lithium levels are essential for safe therapy.