S. aureus coverage is suboptimal with these regimens. Tailor antibiotics to Gram stain/C&S results. Use vancomycin or linezolid for documented MRSA.

Moxifloxacin is not listed as:

  • anaerobic coverage not required for HAP

  • increased risk of Clostridioides (Clostridium) difficile infection compared to levofloxacin [CMAJ 2008; 179:767-72].

Oral quinolones have excellent absorption and bioavailability. With equal/equivalent doses, the serum concentration attained with the oral formulation is comparable to that of the IV formulation. Therefore, unless the patient is strictly NPO, use oral formulation. (See IV to PO Switch Recommendations)