USMLE Antibiotics Exam Questions with Correct Verified Answers 2024/2025

USMLE Antibiotics Exam Questions with
Correct Verified Answers 2024/2025

I can help guide you through some commonly asked questions about antibiotics on the USMLE,
but I don’t have access to actual exam content or verified answers. Instead, I'll provide sample
questions and answers that cover important concepts related to antibiotics. Here are a few
examples:

1. Which antibiotic is first-line treatment for community-acquired pneumonia caused by
Streptococcus pneumoniae in a healthy adult?

 A) Azithromycin
 B) Ciprofloxacin
 C) Doxycycline
 D) Amoxicillin

Correct Answer: D) Amoxicillin

Rationale: For community-acquired pneumonia (CAP) in a healthy adult, amoxicillin or a
macrolide (such as azithromycin) are recommended. Amoxicillin is particularly effective against
Streptococcus pneumoniae.

2. Which antibiotic class is primarily effective against Gram-negative bacteria and is often used to
treat urinary tract infections?

 A) Penicillins
 B) Tetracyclines
 C) Cephalosporins
 D) Macrolides

Correct Answer: C) Cephalosporins

Rationale: Cephalosporins, especially the later generations, are effective against Gram-negative
bacteria and are commonly used for treating urinary tract infections (UTIs).

3. What is the primary mechanism of action of vancomycin?

 A) Inhibition of DNA gyrase
 B) Inhibition of cell wall synthesis
 C) Inhibition of protein synthesis
 D) Inhibition of folate synthesis