SPEX SPEX Pharmacology 1 — Questions and Answers
Question 1: Which mechanism describes how warfarin exerts its anticoagulant effect?
- Inhibiting vitamin K epoxide reductase (Correct answer)
- Blocking thrombin directly
- Activating antithrombin III
- Inhibiting factor Xa only
Correct answer: Inhibiting vitamin K epoxide reductase
Warfarin inhibits vitamin K epoxide reductase, preventing regeneration of reduced vitamin K needed for clotting factor synthesis.
Question 2: A patient on metformin develops lactic acidosis. Which condition most increases this risk?
- Hypertension
- Renal impairment (Correct answer)
- Hyperlipidemia
- Hypothyroidism
Correct answer: Renal impairment
Renal impairment reduces metformin clearance, causing accumulation and increasing the risk of lactic acidosis.
Question 3: Which drug class is first-line for managing acute gout attacks in a patient without contraindications?
- Allopurinol
- Probenecid
- NSAIDs (Correct answer)
- Thiazide diuretics
Correct answer: NSAIDs
NSAIDs such as indomethacin are first-line for acute gout attacks due to rapid anti-inflammatory effect.
Question 4: Which antibiotic class inhibits bacterial cell wall synthesis by binding penicillin-binding proteins?
- Fluoroquinolones
- Macrolides
- Beta-lactams (Correct answer)
- Aminoglycosides
Correct answer: Beta-lactams
Beta-lactam antibiotics bind penicillin-binding proteins (PBPs), inhibiting transpeptidation and bacterial cell wall synthesis.
Question 5: A patient taking an SSRI is started on tramadol for pain. What serious interaction should be anticipated?
- Nephrotoxicity
- Serotonin syndrome (Correct answer)
- Agranulocytosis
- QT prolongation only
Correct answer: Serotonin syndrome
Combining SSRIs with tramadol (which inhibits serotonin reuptake) can precipitate serotonin syndrome due to excess serotonergic activity.
Question 6: Which beta-blocker is considered cardioselective at low doses and preferred in patients with mild asthma?
- Propranolol
- Carvedilol
- Metoprolol (Correct answer)
- Labetalol
Correct answer: Metoprolol
Metoprolol is a beta-1 selective blocker that, at low doses, has less bronchospastic risk compared to non-selective beta-blockers.
SPEX SPEX Pharmacology 1
Which mechanism describes how warfarin exerts its anticoagulant effect?