Pharmacology MCQs
Pharmacology MCQs help learners understand the actions, interactions, uses, and side effects of various drugs. These questions cover pharmacokinetics, pharmacodynamics, drug classifications, and toxicology. Practicing them aids in mastering this crucial medical subject and performing well in exams such as MDCAT, USMLE, FCPS, and NTS.
Q: Aspirin inhibits pain by blocking
A) Sodium channels
B) COX enzymes
C) Beta receptors
D) Calcium receptors
✅ Correct Answer: B
Explanation: Aspirin blocks cyclooxygenase enzymes, reducing prostaglandin synthesis and inflammation.
Q: Paracetamol primarily acts on
A) Central nervous system
B) Liver cells
C) Respiratory tract
D) Kidneys
✅ Correct Answer: A
Explanation: Paracetamol works centrally to reduce fever and pain without strong anti-inflammatory effects.
Q: Beta-blockers lower blood pressure by decreasing
A) Blood glucose
B) Heart rate
C) Oxygen saturation
D) Platelet count
✅ Correct Answer: B
Explanation: Beta-blockers reduce cardiac output by slowing the heart rate.
Q: Warfarin prevents clot formation by inhibiting
A) Vitamin K action
B) Platelet aggregation
C) Fibrin production
D) Calcium absorption
✅ Correct Answer: A
Explanation: Warfarin antagonizes vitamin K, crucial for synthesizing clotting factors.
Q: Atropine is classified as an
A) Antiviral agent
B) Anticholinergic drug
C) Antihistamine
D) Beta agonist
✅ Correct Answer: B
Explanation: Atropine blocks muscarinic receptors, reducing parasympathetic activity.
Q: Naloxone is used to reverse
A) Opioid overdose
B) Asthma attack
C) Hyperglycemia
D) Hypertension
✅ Correct Answer: A
Explanation: Naloxone is an opioid antagonist that rapidly reverses opioid effects.
Q: Diazepam enhances the action of
A) Dopamine
B) Acetylcholine
C) GABA
D) Serotonin
✅ Correct Answer: C
Explanation: Diazepam binds to GABA receptors, enhancing inhibitory neurotransmission.
Q: Antacids relieve heartburn by neutralizing
A) Hormones
B) Gastric acid
C) Enzymes
D) Lipids
✅ Correct Answer: B
Explanation: Antacids raise stomach pH by neutralizing hydrochloric acid.
Q: The bioavailability of oral drugs is influenced by
A) Light exposure
B) First-pass metabolism
C) Skin temperature
D) Injection technique
✅ Correct Answer: B
Explanation: Oral drugs undergo liver metabolism before entering systemic circulation.
Q: Drugs with narrow therapeutic index require
A) Rare usage
B) Close monitoring
C) No prescription
D) High dosage
✅ Correct Answer: B
Explanation: Narrow therapeutic index drugs need careful dose control to avoid toxicity.