NAPLEX QBANK Pharmacology and Drug Mechanisms 3

Question 1

Statins lower cholesterol by inhibiting which enzyme?

Accepted Answer

HMG-CoA reductase

Answer

Squalene synthase

Answer

Lipoprotein lipase

Answer

PCSK9

Question 2

Which opioid is also an NMDA receptor antagonist, useful in neuropathic pain?

Accepted Answer

Methadone

Answer

Morphine

Answer

Codeine

Answer

Hydromorphone

Question 3

The primary mechanism of proton pump inhibitors is:

Accepted Answer

Irreversible inhibition of gastric H+/K+ ATPase

Answer

H2 receptor blockade

Answer

Muscarinic M1 antagonism

Answer

Neutralization of gastric acid

Question 4

Which drug class can cause hyperkalemia due to aldosterone antagonism?

Accepted Answer

Potassium-sparing diuretics

Answer

Thiazide diuretics

Answer

Loop diuretics

Answer

Carbonic anhydrase inhibitors

Question 5

Phenytoin exhibits which pharmacokinetic property at therapeutic doses?

Accepted Answer

Zero-order (nonlinear) elimination

Answer

First-order elimination only

Answer

No protein binding

Answer

Renal elimination unchanged

Question 6

Which mechanism underlies the bronchodilation of tiotropium?

Accepted Answer

Long-acting muscarinic receptor antagonism

Answer

Beta-2 agonism

Answer

Leukotriene receptor blockade

Answer

Mast cell stabilization

Question 7

DPP-4 inhibitors such as sitagliptin lower glucose by:

Accepted Answer

Preventing incretin (GLP-1) degradation

Answer

Blocking renal glucose reabsorption

Answer

Stimulating glucagon release

Answer

Inhibiting hepatic gluconeogenesis directly