Pharmacology MCQs

Pharmacology MCQs test knowledge of drug actions, interactions, classifications, pharmacokinetics, pharmacodynamics, and toxicology. Ideal for MDCAT, USMLE, FCPS, and NTS preparation, these quizzes strengthen medical understanding and boost exam performance through targeted practice.

Q: Effect of beta-blockers on the heart
A) Promote vasodilation
B) Enhance conduction
C) Increase heart rate
D) Decrease contractility
✅ Correct Answer: D
Explanation: Beta-blockers reduce cardiac output by lowering contractility and heart rate.
Q: First-line drug for anaphylaxis
A) Salbutamol
B) Epinephrine
C) Prednisone
D) Diphenhydramine
✅ Correct Answer: B
Explanation: Epinephrine rapidly counteracts bronchoconstriction and hypotension in anaphylaxis.
Q: Reversible cholinesterase inhibitor
A) Atropine
B) Succinylcholine
C) Pralidoxime
D) Neostigmine
✅ Correct Answer: D
Explanation: Neostigmine temporarily inhibits acetylcholinesterase, increasing acetylcholine levels.
Q: Metformin primarily acts by
A) Blocking glucagon receptors
B) Inhibiting gluconeogenesis
C) Stimulating insulin secretion
D) Promoting glycogenolysis
✅ Correct Answer: B
Explanation: Metformin lowers blood glucose by reducing hepatic glucose production.
Q: Drug causing disulfiram-like reaction with alcohol
A) Azithromycin
B) Metronidazole
C) Ceftriaxone
D) Amoxicillin
✅ Correct Answer: B
Explanation: Metronidazole inhibits aldehyde dehydrogenase, leading to a reaction with alcohol.
Q: Preferred route for administering insulin
A) Intravenous
B) Oral
C) Subcutaneous
D) Intramuscular
✅ Correct Answer: C
Explanation: Insulin is administered subcutaneously due to degradation in the GI tract.
Q: Side effect associated with chronic aspirin use
A) Gastric ulceration
B) Palpitations
C) Skin rash
D) Hypoglycemia
✅ Correct Answer: A
Explanation: Aspirin irritates the gastric mucosa and can lead to ulcer formation.
Q: Atypical antipsychotic with least extrapyramidal effects
A) Haloperidol
B) Fluphenazine
C) Clozapine
D) Chlorpromazine
✅ Correct Answer: C
Explanation: Clozapine has minimal effects on dopamine D2 receptors, reducing movement disorders.
Q: Laxative increasing fecal bulk
A) Magnesium hydroxide
B) Lactulose
C) Psyllium
D) Bisacodyl
✅ Correct Answer: C
Explanation: Psyllium absorbs water in the intestine, forming a bulky, gel-like stool.
Q: Antifungal targeting ergosterol synthesis
A) Griseofulvin
B) Amphotericin B
C) Fluconazole
D) Nystatin
✅ Correct Answer: C
Explanation: Fluconazole inhibits the fungal cytochrome P450 enzyme needed for ergosterol synthesis.