NAPLEX QBANK Pharmacology and Drug Mechanisms 4

Question 1

Which antibiotic class inhibits bacterial DNA gyrase and topoisomerase IV?

Accepted Answer

Fluoroquinolones

Answer

Fluoroquinolones target DNA gyrase and topoisomerase IV, blocking DNA replication.

Question 2

The antidote for benzodiazepine overdose is:

Accepted Answer

Flumazenil

Answer

Flumazenil is a competitive GABA-A benzodiazepine receptor antagonist.

Question 3

Which mechanism explains aspirin's antiplatelet action?

Accepted Answer

Irreversible acetylation of COX-1 blocking thromboxane A2

Answer

Aspirin irreversibly acetylates platelet COX-1, reducing thromboxane A2.

Question 4

Allopurinol lowers uric acid by inhibiting which enzyme?

Accepted Answer

Xanthine oxidase

Answer

Allopurinol inhibits xanthine oxidase, decreasing uric acid production.

Question 5

Which drug's toxicity is treated with N-acetylcysteine?

Accepted Answer

Acetaminophen

Answer

N-acetylcysteine replenishes glutathione to detoxify acetaminophen's NAPQI metabolite.

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