🏥 NCLEX Pharmacology MCQs (Set 2: Q50–100)
Pharmacology is one of the most tested areas in the NCLEX-RN exam, and mastering drug knowledge is essential for every nursing student. In this guide, we bring you NCLEX Pharmacology MCQs Part 2 (51–100), complete with correct answers and detailed explanations.
These questions cover cardiovascular drugs, insulin types, anticoagulants, antibiotics, psychiatric medications, and endocrine drugs—all important for NCLEX and nursing exams worldwide.
If you haven’t already, check out 👉 NCLEX Pharmacology MCQs Part 1 (1–50).
51. Which class of drugs is used as the first-line treatment for hypertension?
A) Beta-blockers
B) ACE inhibitors
C) Calcium channel blockers
D) Diuretics
✅ Correct Answer: D) Diuretics
💡 Explanation: Thiazide diuretics are commonly prescribed as the first-line treatment for primary hypertension. They help reduce blood pressure by decreasing fluid volume. ACE inhibitors or beta-blockers may also be used depending on comorbidities.
52. Which medication is the antidote for opioid overdose?
A) Flumazenil
B) Atropine
C) Naloxone
D) Protamine sulfate
✅ Correct Answer: C) Naloxone
💡 Explanation: Naloxone is an opioid antagonist that reverses respiratory depression and sedation caused by opioid overdose. It works rapidly but may require repeat dosing.
53. Which of the following antibiotics can cause teeth discoloration in children?
A) Penicillin
B) Tetracycline
C) Erythromycin
D) Cephalosporins
✅ Correct Answer: B) Tetracycline
💡 Explanation: Tetracyclines bind to calcium in developing teeth and bones, causing permanent yellow-brown discoloration. They should be avoided in children under 8 years and pregnant women.
54. Which medication is used to prevent organ rejection in transplant patients?
A) Methotrexate
B) Cyclosporine
C) Azithromycin
D) Prednisone
✅ Correct Answer: B) Cyclosporine
💡 Explanation: Cyclosporine is an immunosuppressant that inhibits T-cell activation, reducing the risk of transplant rejection. Blood levels must be monitored to avoid nephrotoxicity.
55. Which vitamin deficiency is linked with prolonged use of isoniazid (INH) in tuberculosis treatment?
A) Vitamin B1
B) Vitamin B6
C) Vitamin B12
D) Vitamin C
✅ Correct Answer: B) Vitamin B6
💡 Explanation: Isoniazid interferes with pyridoxine (B6) metabolism, leading to peripheral neuropathy. Supplementation with B6 is recommended during INH therapy.
56. Which drug is classified as a loop diuretic?
A) Hydrochlorothiazide
B) Spironolactone
C) Furosemide
D) Acetazolamide
✅ Correct Answer: C) Furosemide
💡 Explanation: Furosemide (Lasix) is a loop diuretic that acts on the loop of Henle to increase urine output. It is used in heart failure, pulmonary edema, and hypertension.
57. Which of the following is an anticoagulant that requires INR monitoring?
A) Aspirin
B) Clopidogrel
C) Warfarin
D) Heparin
✅ Correct Answer: C) Warfarin
💡 Explanation: Warfarin inhibits vitamin K-dependent clotting factors. Regular monitoring of the INR (International Normalized Ratio) is necessary to balance effectiveness with bleeding risk.
58. What is the main adverse effect of aminoglycosides (e.g., gentamicin)?
A) Nephrotoxicity and ototoxicity
B) Hepatotoxicity
C) Photosensitivity
D) Hypoglycemia
✅ Correct Answer: A) Nephrotoxicity and ototoxicity
💡 Explanation: Aminoglycosides can damage the kidneys (nephrotoxicity) and the inner ear (ototoxicity). Monitoring renal function and drug levels is essential.
59. Which drug is used as an emergency treatment for anaphylaxis?
A) Epinephrine
B) Hydrocortisone
C) Diphenhydramine
D) Salbutamol
✅ Correct Answer: A) Epinephrine
💡 Explanation: Intramuscular epinephrine is the first-line treatment for anaphylaxis. It counteracts bronchoconstriction, hypotension, and swelling by stimulating alpha and beta adrenergic receptors.
60. Which of the following drugs is used in the management of bipolar disorder?
A) Lithium
B) Diazepam
C) Fluoxetine
D) Phenytoin
✅ Correct Answer: A) Lithium
💡 Explanation: Lithium is a mood stabilizer commonly used in bipolar disorder. Serum levels must be closely monitored due to its narrow therapeutic index and risk of toxicity.
NCLEX Pharmacology MCQs (Part 3: Questions 61–70)
61. Which drug is commonly used for long-term prevention of asthma attacks?
A) Salbutamol (Albuterol)
B) Montelukast
C) Epinephrine
D) Ipratropium
✅ Correct Answer: B) Montelukast
💡 Explanation: Montelukast is a leukotriene receptor antagonist used for long-term asthma control. Salbutamol is for acute relief, not prevention.
62. Which medication is contraindicated in pregnancy due to risk of fetal abnormalities?
A) Penicillin
B) Tetracycline
C) Paracetamol
D) Amoxicillin
✅ Correct Answer: B) Tetracycline
💡 Explanation: Tetracyclines cross the placenta and affect fetal bone and teeth development. They are avoided in pregnancy.
63. Which drug is used as a proton pump inhibitor (PPI) for peptic ulcer disease?
A) Ranitidine
B) Omeprazole
C) Sucralfate
D) Metoclopramide
✅ Correct Answer: B) Omeprazole
💡 Explanation: Omeprazole reduces gastric acid secretion by inhibiting the H+/K+ ATPase pump, making it effective in treating GERD and ulcers.
64. Which antiarrhythmic drug is known to cause pulmonary fibrosis as a side effect?
A) Digoxin
B) Amiodarone
C) Verapamil
D) Atenolol
✅ Correct Answer: B) Amiodarone
💡 Explanation: Amiodarone is highly effective in treating arrhythmias but has severe side effects, including pulmonary fibrosis, thyroid dysfunction, and skin changes.
65. Which class of drugs is most commonly used to lower cholesterol levels?
A) Beta-blockers
B) Statins
C) Diuretics
D) ACE inhibitors
✅ Correct Answer: B) Statins
💡 Explanation: Statins (e.g., atorvastatin, simvastatin) inhibit HMG-CoA reductase, lowering LDL cholesterol and reducing cardiovascular risk.
66. What is the main adverse effect of corticosteroids when used long-term?
A) Hypoglycemia
B) Immunosuppression
C) Hyperpigmentation
D) Alopecia
✅ Correct Answer: B) Immunosuppression
💡 Explanation: Long-term corticosteroid use weakens the immune system, increases infection risk, causes osteoporosis, and may lead to Cushing’s syndrome.
67. Which drug is used as an antidote for benzodiazepine overdose?
A) Naloxone
B) Flumazenil
C) Protamine sulfate
D) Atropine
✅ Correct Answer: B) Flumazenil
💡 Explanation: Flumazenil is a benzodiazepine receptor antagonist that reverses sedative effects of benzodiazepines like diazepam or lorazepam.
68. Which insulin is considered long-acting?
A) Insulin lispro
B) Insulin aspart
C) Insulin glargine
D) Regular insulin
✅ Correct Answer: C) Insulin glargine
💡 Explanation: Insulin glargine is a long-acting insulin that provides steady blood sugar control for up to 24 hours. Lispro and aspart are rapid-acting, while regular insulin is short-acting.
69. Which of the following medications is used for the treatment of Parkinson’s disease?
A) Levodopa-Carbidopa
B) Diazepam
C) Fluoxetine
D) Haloperidol
✅ Correct Answer: A) Levodopa-Carbidopa
💡 Explanation: Levodopa replenishes dopamine in the brain, while carbidopa prevents its breakdown before reaching the brain. Together, they are the cornerstone of Parkinson’s treatment.
70. Which antibiotic is known to cause tendon rupture as a rare but serious side effect?
A) Penicillin
B) Ciprofloxacin
C) Vancomycin
D) Azithromycin
✅ Correct Answer: B) Ciprofloxacin
💡 Explanation: Fluoroquinolones like ciprofloxacin may cause tendon damage, especially the Achilles tendon, and are used with caution in elderly patients.
71. Which vitamin deficiency can be caused by long-term use of isoniazid (INH)?
A) Vitamin B6 (Pyridoxine)
B) Vitamin B12
C) Vitamin D
D) Vitamin C
✅ Correct Answer: A) Vitamin B6 (Pyridoxine)
💡 Explanation: INH therapy interferes with pyridoxine metabolism, leading to peripheral neuropathy unless supplementation is provided.
72. Which anticoagulant requires frequent INR monitoring?
A) Heparin
B) Dabigatran
C) Warfarin
D) Enoxaparin
✅ Correct Answer: C) Warfarin
💡 Explanation: Warfarin has a narrow therapeutic window and requires regular INR testing to avoid bleeding complications.
73. Which drug is considered the first-line treatment for anaphylaxis?
A) Epinephrine
B) Hydrocortisone
C) Diphenhydramine
D) Oxygen
✅ Correct Answer: A) Epinephrine
💡 Explanation: Intramuscular epinephrine is the immediate life-saving drug in anaphylaxis, as it reverses airway obstruction and shock.
74. Which electrolyte imbalance is a known side effect of loop diuretics (e.g., furosemide)?
A) Hyperkalemia
B) Hypokalemia
C) Hypernatremia
D) Hypocalcemia
✅ Correct Answer: B) Hypokalemia
💡 Explanation: Loop diuretics increase potassium excretion, leading to hypokalemia, muscle weakness, and arrhythmias if not monitored.
75. What is the drug of choice for status epilepticus?
A) Phenytoin
B) Lorazepam
C) Valproate
D) Carbamazepine
✅ Correct Answer: B) Lorazepam
💡 Explanation: IV lorazepam is preferred for rapid seizure control, followed by longer-acting agents like phenytoin.
76. Which of the following is a selective serotonin reuptake inhibitor (SSRI)?
A) Amitriptyline
B) Fluoxetine
C) Lithium
D) Diazepam
✅ Correct Answer: B) Fluoxetine
💡 Explanation: Fluoxetine is an SSRI commonly used in depression and anxiety, with fewer side effects compared to tricyclics.
77. Which antihypertensive drug is contraindicated in pregnancy?
A) Methyldopa
B) ACE inhibitors
C) Labetalol
D) Hydralazine
✅ Correct Answer: B) ACE inhibitors
💡 Explanation: ACE inhibitors can cause fetal renal damage and are avoided during pregnancy. Safer options include methyldopa and labetalol.
78. Which drug is most effective for acute migraine attacks?
A) Sumatriptan
B) Ibuprofen
C) Propranolol
D) Verapamil
✅ Correct Answer: A) Sumatriptan
💡 Explanation: Triptans like sumatriptan are serotonin agonists that relieve acute migraine by causing cranial vasoconstriction.
79. What is the mechanism of action of proton pump inhibitors (PPIs)?
A) Block histamine H2 receptors
B) Block H+/K+ ATPase pump
C) Neutralize gastric acid
D) Stimulate bicarbonate release
✅ Correct Answer: B) Block H+/K+ ATPase pump
💡 Explanation: PPIs such as omeprazole irreversibly block gastric proton pumps, reducing stomach acid production.
80. Which drug is an example of a calcium channel blocker used in hypertension?
A) Losartan
B) Amlodipine
C) Atenolol
D) Digoxin
✅ Correct Answer: B) Amlodipine
💡 Explanation: Amlodipine relaxes vascular smooth muscles by blocking calcium channels, lowering blood pressure.
81. Which antibiotic is commonly associated with tendon rupture?
A) Amoxicillin
B) Ciprofloxacin
C) Doxycycline
D) Azithromycin
✅ Correct Answer: B) Ciprofloxacin
💡 Explanation: Fluoroquinolones (like ciprofloxacin) can cause tendonitis and tendon rupture, especially in older adults.
82. Which medication is used to reverse the effects of opioid overdose?
A) Naloxone
B) Flumazenil
C) Protamine sulfate
D) Atropine
✅ Correct Answer: A) Naloxone
💡 Explanation: Naloxone is an opioid antagonist that rapidly reverses respiratory depression caused by opioid overdose.
83. Which side effect is most concerning in patients taking clozapine?
A) Dry mouth
B) Agranulocytosis
C) Weight gain
D) Sedation
✅ Correct Answer: B) Agranulocytosis
💡 Explanation: Clozapine requires regular WBC monitoring due to the risk of life-threatening agranulocytosis.
84. What is the antidote for benzodiazepine overdose?
A) Naloxone
B) Flumazenil
C) Activated charcoal
D) Atropine
✅ Correct Answer: B) Flumazenil
💡 Explanation: Flumazenil is a GABA receptor antagonist that reverses sedation and respiratory depression caused by benzodiazepines.
85. Which diuretic is potassium-sparing?
A) Furosemide
B) Hydrochlorothiazide
C) Spironolactone
D) Mannitol
✅ Correct Answer: C) Spironolactone
💡 Explanation: Spironolactone is an aldosterone antagonist that spares potassium, unlike loop and thiazide diuretics.
86. Which drug is most effective in lowering LDL cholesterol?
A) Statins (e.g., Atorvastatin)
B) Fibrates
C) Niacin
D) Ezetimibe
✅ Correct Answer: A) Statins (e.g., Atorvastatin)
💡 Explanation: Statins inhibit HMG-CoA reductase and are first-line therapy for reducing LDL cholesterol and cardiovascular risk.
87. Which drug is used in the management of organophosphate poisoning?
A) Atropine + Pralidoxime
B) Naloxone
C) Flumazenil
D) Protamine sulfate
✅ Correct Answer: A) Atropine + Pralidoxime
💡 Explanation: Atropine blocks muscarinic receptors while pralidoxime reactivates acetylcholinesterase inhibited by organophosphates.
88. Which of the following medications can cause gingival hyperplasia?
A) Phenytoin
B) Lithium
C) Valproic acid
D) Carbamazepine
✅ Correct Answer: A) Phenytoin
💡 Explanation: Phenytoin is associated with gum hypertrophy, hirsutism, and folate deficiency.
89. Which drug is a beta-blocker used in heart failure?
A) Atenolol
B) Carvedilol
C) Amlodipine
D) Digoxin
✅ Correct Answer: B) Carvedilol
💡 Explanation: Carvedilol is a non-selective beta-blocker with alpha-blocking activity, beneficial in reducing mortality in heart failure.
90. What is the primary adverse effect of aminoglycosides (e.g., gentamicin)?
A) Hepatotoxicity
B) Ototoxicity and nephrotoxicity
C) Pulmonary fibrosis
D) Hypoglycemia
✅ Correct Answer: B) Ototoxicity and nephrotoxicity
💡 Explanation: Aminoglycosides accumulate in the kidney and inner ear, causing irreversible hearing loss and renal damage.
91. Which insulin has the fastest onset of action?
A) Regular insulin
B) NPH insulin
C) Insulin lispro
D) Insulin glargine
✅ Correct Answer: C) Insulin lispro
💡 Explanation: Insulin lispro is a rapid-acting insulin with onset within 15 minutes, making it ideal for controlling post-meal glucose spikes.
92. Which of the following medications is contraindicated in pregnancy?
A) Methyldopa
B) ACE inhibitors
C) Labetalol
D) Hydralazine
✅ Correct Answer: B) ACE inhibitors
💡 Explanation: ACE inhibitors cause fetal renal damage and are contraindicated in pregnancy.
93. What is the mechanism of action of omeprazole?
A) Blocks H2 receptors
B) Inhibits proton pump (H+/K+ ATPase)
C) Neutralizes gastric acid
D) Coats stomach lining
✅ Correct Answer: B) Inhibits proton pump (H+/K+ ATPase)
💡 Explanation: Omeprazole is a proton pump inhibitor (PPI) that blocks acid secretion in the stomach.
94. Which drug is used as a first-line therapy for absence seizures?
A) Phenytoin
B) Valproic acid
C) Ethosuximide
D) Carbamazepine
✅ Correct Answer: C) Ethosuximide
💡 Explanation: Ethosuximide is the drug of choice for absence seizures due to its effect on T-type calcium channels.
95. Which anticoagulant requires INR monitoring?
A) Heparin
B) Warfarin
C) Dabigatran
D) Apixaban
✅ Correct Answer: B) Warfarin
💡 Explanation: Warfarin’s therapeutic range is monitored using INR (2.0–3.0 for most conditions).
96. Which adverse effect is associated with isoniazid (INH)?
A) Hepatotoxicity & peripheral neuropathy
B) Nephrotoxicity
C) Pulmonary fibrosis
D) Agranulocytosis
✅ Correct Answer: A) Hepatotoxicity & peripheral neuropathy
💡 Explanation: INH can cause liver toxicity and B6 deficiency leading to neuropathy. Pyridoxine supplementation is recommended.
97. Which drug is most commonly associated with lactic acidosis in diabetic patients?
A) Glibenclamide
B) Metformin
C) Insulin
D) Sitagliptin
✅ Correct Answer: B) Metformin
💡 Explanation: Metformin can rarely cause lactic acidosis, especially in patients with kidney disease.
98. Which medication is an antiplatelet drug?
A) Warfarin
B) Heparin
C) Aspirin
D) Enoxaparin
✅ Correct Answer: C) Aspirin
💡 Explanation: Aspirin irreversibly inhibits COX-1, reducing platelet aggregation and preventing clot formation.
99. Which antipsychotic is most associated with metabolic syndrome (weight gain, diabetes, dyslipidemia)?
A) Haloperidol
B) Risperidone
C) Olanzapine
D) Chlorpromazine
✅ Correct Answer: C) Olanzapine
💡 Explanation: Olanzapine and clozapine are strongly linked to metabolic complications.
100. Which drug is commonly used to treat hyperthyroidism?
A) Levothyroxine
B) Propylthiouracil (PTU)
C) Liothyronine
D) Hydrocortisone
✅ Correct Answer: B) Propylthiouracil (PTU)
💡 Explanation: PTU inhibits thyroid hormone synthesis and peripheral conversion of T4 to T3, making it useful in hyperthyroidism.
That completes NCLEX Pharmacology MCQs Part 2 (51–100) ✅. By practicing these questions with explanations, you can strengthen your pharmacology concepts and boost your NCLEX-RN score.
NCLEX Pharmacology MCQs Part 3
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