Inpatient treatment of community-acquired pneumonia in the elderly commonly includes which regimen?

• A. Amoxicillin alone
• B. Azithromycin monotherapy
• C. Azithromycin plus ceftriaxone
• D. Doxycycline and amoxicillin

Answer: (C)

Inpatient treatment of community-acquired pneumonia in older adults aims to cover both typical bacteria (like Streptococcus pneumoniae and Haemophilus influenzae) and atypical pathogens (such as Mycoplasma and Chlamydophila), since hospitalized patients often have more severe disease and varied causative organisms. Using a beta-lactam given intravenously, like ceftriaxone, provides strong coverage against typical bacteria, while adding a macrolide such as azithromycin targets atypicals and also helps cover Legionella. This combination—ceftriaxone plus azithromycin—offers broad, synergistic coverage in the hospital setting, which is why it is a common and appropriate regimen for elderly inpatients with CAP.

Amoxicillin alone may miss atypicals and is not ideal for IV inpatient use. Azithromycin alone covers atypicals but may miss many typical pathogens. A doxycycline plus amoxicillin pair can cover some organisms but does not align with the standard inpatient approach of combining a beta-lactam with a macrolide to ensure broad, empiric coverage in older adults with CAP.