USMLE Step 2 Antibiotics and Treatments Practice Exam 2025 – Comprehensive All-in-One Guide for Exam Success!

Azithromycin is commonly used for the empiric treatment of community-acquired pneumonia (CAP) in adults due to its effectiveness against common pathogens responsible for this condition, particularly atypical bacteria such as Mycoplasma pneumoniae and Chlamydophila pneumoniae. It is also effective against Streptococcus pneumoniae, one of the most prevalent bacteria causing CAP.

The use of azithromycin as a macrolide antibiotic offers advantages such as good tissue penetration and a favorable side effect profile, making it a preferred choice in many clinical settings. Its coverage broadens the range of potential pathogens in CAP treatment, ensuring that patients receive a broad-spectrum antibiotic that can address both typical and atypical organisms.

In contrast, while options like amoxicillin may also be used for straightforward cases of pneumonia, they primarily target typical organisms and may not adequately cover the atypical ones without additional therapies. Other choices like ciprofloxacin and clindamycin might be used in specific situations but are not typically first-line agents for empiric treatment of CAP in adults.