FPGEE Pharmacology 2 — Questions and Answers
Question 1: Which mechanism best describes the action of beta-lactam antibiotics?
- Inhibit bacterial cell wall synthesis by binding penicillin-binding proteins (Correct answer)
- Block the 30S ribosomal subunit to inhibit protein synthesis
- Disrupt the bacterial cell membrane integrity
- Inhibit DNA gyrase and topoisomerase IV
Correct answer: Inhibit bacterial cell wall synthesis by binding penicillin-binding proteins
Beta-lactams inhibit transpeptidation by covalently binding penicillin-binding proteins (PBPs), preventing cross-linking of peptidoglycan.
Question 2: A patient on warfarin is started on rifampin. What pharmacokinetic interaction is expected?
- Decreased warfarin effect due to CYP induction (Correct answer)
- Increased warfarin effect due to CYP inhibition
- Decreased warfarin effect due to reduced absorption
- Increased warfarin effect due to protein binding displacement
Correct answer: Decreased warfarin effect due to CYP induction
Rifampin is a potent CYP450 inducer that increases warfarin metabolism, significantly reducing its anticoagulant effect.
Question 3: Which adrenergic receptor subtype mediates bronchodilation?
- Beta-2 (Correct answer)
- Alpha-1
- Beta-1
- Alpha-2
Correct answer: Beta-2
Beta-2 adrenergic receptors in bronchial smooth muscle mediate relaxation and bronchodilation when stimulated.
Question 4: What is the primary mechanism of action of thiazide diuretics?
- Inhibit Na+/Cl- cotransporter in the distal convoluted tubule (Correct answer)
- Block Na+/K+/2Cl- cotransporter in the loop of Henle
- Inhibit carbonic anhydrase in the proximal tubule
- Block aldosterone receptors in the collecting duct
Correct answer: Inhibit Na+/Cl- cotransporter in the distal convoluted tubule
Thiazides inhibit the NCC (Na+/Cl-) cotransporter in the distal convoluted tubule, reducing sodium reabsorption.
Question 5: A patient with opioid overdose presents with pinpoint pupils and respiratory depression. Which agent is the treatment of choice?
- Naloxone (Correct answer)
- Flumazenil
- N-acetylcysteine
- Physostigmine
Correct answer: Naloxone
Naloxone is a competitive opioid antagonist at mu, kappa, and delta receptors and rapidly reverses opioid toxidrome.
Question 6: Which antiepileptic drug acts primarily by blocking voltage-gated sodium channels in their inactivated state?
- Phenytoin (Correct answer)
- Ethosuximide
- Valproic acid
- Benzodiazepines
Correct answer: Phenytoin
Phenytoin stabilizes the inactivated state of voltage-gated Na+ channels, preventing repetitive neuronal firing.
Question 7: ACE inhibitors are contraindicated in pregnancy primarily because they cause which fetal complication?
- Renal dysgenesis and oligohydramnios (Correct answer)
- Neural tube defects
- Cardiac septal defects
- Limb reduction abnormalities
Correct answer: Renal dysgenesis and oligohydramnios
ACE inhibitors reduce fetal renal perfusion, leading to renal tubular dysgenesis, oligohydramnios, and fetal death, especially in the 2nd and 3rd trimester.
FPGEE Pharmacology 2
Which mechanism best describes the action of beta-lactam antibiotics?