GPAT (Graduate Pharmacy Aptitude Test) is one of the most important competitive exams for pharmacy students. Pharmacology carries significant weightage in GPAT. Below are 10 important and exam-oriented MCQs with correct answers and detailed explanations to strengthen your preparation for GPAT 2026.
1. Which of the following drugs is a selective β1-adrenergic receptor blocker?
A. Propranolol
B. Atenolol
C. Pindolol
D. Carvedilol
Answer: B. Atenolol
Explanation: Atenolol is a selective β1-blocker that primarily acts on the heart and is used in hypertension, angina, and arrhythmias. Propranolol and pindolol are non-selective β-blockers.
2. Aspirin produces its antiplatelet effect by:
A. Inhibiting thromboxane A2 synthesis
B. Blocking ADP receptors
C. Inhibiting vitamin K synthesis
D. Activating plasminogen
Answer: A. Inhibiting thromboxane A2 synthesis
Explanation: Aspirin irreversibly inhibits cyclooxygenase (COX-1) in platelets, reducing thromboxane A2 formation, which decreases platelet aggregation.
3. Which of the following drugs is used as an antidote for organophosphate poisoning?
A. Naloxone
B. Atropine
C. Flumazenil
D. Protamine
Answer: B. Atropine
Explanation: Organophosphates inhibit acetylcholinesterase, leading to excess acetylcholine. Atropine blocks muscarinic receptors and counteracts cholinergic symptoms.
4. The drug of choice for anaphylactic shock is:
A. Dopamine
B. Hydrocortisone
C. Epinephrine
D. Salbutamol
Answer: C. Epinephrine
Explanation: Epinephrine (adrenaline) is the drug of choice in anaphylaxis because it causes bronchodilation, vasoconstriction, and increases cardiac output.
5. Which antihypertensive drug is an ACE inhibitor?
A. Losartan
B. Enalapril
C. Amlodipine
D. Atenolol
Answer: B. Enalapril
Explanation: Enalapril inhibits angiotensin-converting enzyme (ACE), reducing formation of angiotensin II and lowering blood pressure.
6. Tetracyclines should not be given in children because they:
A. Cause hypoglycemia
B. Damage kidney
C. Stain teeth and affect bone growth
D. Cause hypertension
Answer: C. Stain teeth and affect bone growth
Explanation: Tetracyclines deposit in bones and teeth, causing permanent discoloration and enamel hypoplasia in children.
7. Which of the following is a loop diuretic?
A. Hydrochlorothiazide
B. Spironolactone
C. Furosemide
D. Acetazolamide
Answer: C. Furosemide
Explanation: Furosemide acts on the thick ascending limb of the loop of Henle and produces potent diuresis.
8. Warfarin acts by:
A. Inhibiting thrombin directly
B. Blocking vitamin K epoxide reductase
C. Activating plasminogen
D. Inhibiting platelet aggregation
Answer: B. Blocking vitamin K epoxide reductase
Explanation: Warfarin inhibits vitamin K epoxide reductase, preventing activation of clotting factors II, VII, IX, and X.
9. Which of the following drugs is a proton pump inhibitor?
A. Ranitidine
B. Omeprazole
C. Famotidine
D. Sucralfate
Answer: B. Omeprazole
Explanation: Omeprazole inhibits H+/K+ ATPase (proton pump) in gastric parietal cells, reducing gastric acid secretion.
10. The therapeutic effect of benzodiazepines is due to:
A. Blocking NMDA receptors
B. Enhancing GABA action
C. Inhibiting serotonin reuptake
D. Blocking dopamine receptors
Answer: B. Enhancing GABA action
Explanation: Benzodiazepines enhance the effect of GABA at GABA-A receptors, increasing chloride influx and producing anxiolytic and sedative effects.
Conclusion
These pharmacology MCQs are highly important for GPAT 2026 preparation. Regular practice of conceptual and mechanism-based questions will improve accuracy and speed in the exam. Stay consistent and revise drug mechanisms thoroughly.