NAPLEX QBANK Pharmacology and Mechanism of Action 5

Question 1

Which mechanism explains the action of direct oral anticoagulant apixaban?

Accepted Answer

Direct factor Xa inhibition

Answer

Apixaban directly and reversibly inhibits factor Xa.

Question 2

Dabigatran differs from apixaban in that it:

Accepted Answer

Directly inhibits thrombin (IIa)

Answer

Dabigatran is a direct thrombin inhibitor, reversed by idarucizumab.

Question 3

The mechanism of action of SGLT2 inhibitors (e.g., empagliflozin) is:

Accepted Answer

Blocking renal proximal tubule glucose reabsorption

Answer

SGLT2 inhibitors block glucose reabsorption in the proximal tubule, increasing urinary glucose excretion.

Question 4

GLP-1 receptor agonists (e.g., semaglutide) lower glucose by:

Accepted Answer

Enhancing glucose-dependent insulin secretion and slowing gastric emptying

Answer

GLP-1 agonists augment glucose-dependent insulin release, suppress glucagon, and slow gastric emptying.

Question 5

Which drug class inhibits the breakdown of incretins to lower blood glucose?

Accepted Answer

DPP-4 inhibitors (e.g., sitagliptin)

Answer

DPP-4 inhibitors prevent degradation of GLP-1 and GIP, prolonging incretin effects.

NAPLEX QBANK Practice Test