Repeated USMLE Questions Step 1- Review- 96- Pharmacology

Q- A farmer presents to the emergency room diagnosed with pesticide toxicity. Which one of the following is a cholinesterase activator?

A- Edrophonium

B- Isoflurophate

C- Pilocarpine

D- Pralidoxime

D- Pralidoxime- Pralidoxime, also known as 2-PAM (2-Pyridine Aldoxime Methyl Chloride), is a cholinesterase reactivator. It works by reactivating acetylcholinesterase that has been inhibited by certain organophosphate pesticides or nerve agents, thereby reversing their toxic effects. It is commonly used in the treatment of organophosphate poisoning.


Q- Which one of the following medications acts by activation of alpha-2 adrenergic receptors?

A- Clonidine

B- Enalapril

C- Labetalol

D- Phentolamine

A- Clonidine- It is used in the treatment of hypertension, ADHD and certain withdrawal symptoms. It acts primarily by activation alpha-2 adrenergic receptors. Enalapril is an angiotensin-converting enzyme inhibitor. Labetalol is an alpha- and beta-adrenergic blocker. Phentolamine is an alpha-adrenergic blocker.


Q- Which one of the following antibiotics acts by inhibiting bacterial RNA synthesis?

A- Chloramphenicol

B- Erythromycin

C- Imipenem

D- Rifampin

D- Rifampin- Rifampin inhibits bacterial RNA synthesis by binding to the β subunit of bacterial DNA-dependent RNA polymerase, thereby blocking transcription initiation and RNA chain elongation. It is commonly used in the treatment of tuberculosis and other bacterial infections.

More Pharmacology MCQs

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