FPGEE Pharmacology 3 — Questions and Answers
Question 1: Metformin's primary mechanism for lowering blood glucose in type 2 diabetes involves which action?
- Decreasing hepatic glucose production via AMPK activation (Correct answer)
- Stimulating pancreatic beta cells to release more insulin
- Blocking alpha-glucosidase to reduce carbohydrate absorption
- Increasing renal glucose excretion via SGLT2 inhibition
Correct answer: Decreasing hepatic glucose production via AMPK activation
Metformin activates AMPK, which decreases hepatic gluconeogenesis and glycogenolysis, lowering fasting glucose without causing hypoglycemia.
Question 2: Which drug class is first-line for treating Helicobacter pylori eradication in combination with antibiotics?
- Proton pump inhibitors (Correct answer)
- H2 receptor antagonists
- Antacids
- Bismuth subsalicylate alone
Correct answer: Proton pump inhibitors
PPIs raise gastric pH, enhancing the activity of clarithromycin and amoxicillin in H. pylori triple therapy regimens.
Question 3: A patient taking a selective serotonin reuptake inhibitor (SSRI) is prescribed tramadol for pain. What serious interaction risk exists?
- Serotonin syndrome (Correct answer)
- Hypertensive crisis
- QT prolongation
- Neuroleptic malignant syndrome
Correct answer: Serotonin syndrome
Tramadol inhibits serotonin reuptake, and combined with an SSRI this can precipitate life-threatening serotonin syndrome.
Question 4: Which pharmacokinetic parameter describes the fraction of an administered dose that reaches systemic circulation unchanged?
- Bioavailability (F) (Correct answer)
- Volume of distribution (Vd)
- Clearance (CL)
- Half-life (t½)
Correct answer: Bioavailability (F)
Bioavailability (F) accounts for first-pass metabolism, absorption efficiency, and other factors that reduce systemic drug availability.
Question 5: Heparin's anticoagulant activity is primarily due to which mechanism?
- Potentiation of antithrombin III to inhibit thrombin and factor Xa (Correct answer)
- Direct inhibition of thrombin active site
- Inhibition of vitamin K-dependent clotting factor synthesis
- Blocking platelet glycoprotein IIb/IIIa receptors
Correct answer: Potentiation of antithrombin III to inhibit thrombin and factor Xa
Heparin binds antithrombin III, causing a conformational change that dramatically accelerates its inhibition of thrombin and factor Xa.
Question 6: Which aminoglycoside toxicity is most associated with irreversible damage?
- Ototoxicity (Correct answer)
- Nephrotoxicity
- Neuromuscular blockade
- Hepatotoxicity
Correct answer: Ototoxicity
Aminoglycosides cause destruction of cochlear and vestibular hair cells, which do not regenerate, leading to permanent hearing loss.
Question 7: Which enzyme is inhibited by statins, reducing endogenous cholesterol synthesis?
- HMG-CoA reductase (Correct answer)
- Acyl-CoA cholesterol acyltransferase
- Lipoprotein lipase
- Cholesterol 7-alpha-hydroxylase
Correct answer: HMG-CoA reductase
Statins competitively inhibit HMG-CoA reductase, the rate-limiting enzyme in the mevalonate pathway for cholesterol biosynthesis.
FPGEE Pharmacology 3
Metformin's primary mechanism for lowering blood glucose in type 2 diabetes involves which action?