Does Levaquin Treat Staph Infections?
Yes, levofloxacin (Levaquin) is FDA-approved and effective for treating methicillin-susceptible Staphylococcus aureus (MSSA) infections, but it should NOT be used as monotherapy for staphylococcal infections when implants are present or in severe infections, and it is NOT appropriate for MRSA. 1
FDA-Approved Indications for Staphylococcal Infections
Levofloxacin is specifically FDA-approved for treating infections caused by methicillin-susceptible Staphylococcus aureus in the following conditions 1:
- Nosocomial pneumonia (with adjunctive therapy as clinically indicated) 1
- Community-acquired pneumonia (7-14 day regimen) 1
- Complicated skin and skin structure infections 1
- Uncomplicated skin and skin structure infections (mild to moderate, including abscesses, cellulitis, furuncles, impetigo, pyoderma, wound infections) 1
- Chronic bacterial prostatitis (for methicillin-susceptible S. epidermidis) 1
Critical Limitations and Contraindications
MRSA Coverage
Levofloxacin is NOT appropriate for MRSA infections. 2 For MRSA pneumonia or other MRSA infections, vancomycin, teicoplanin, or linezolid should be used instead 2. Guidelines consistently recommend vancomycin or linezolid for empiric MRSA coverage in severe infections 3.
Monotherapy Restrictions
Levofloxacin monotherapy against staphylococci is NOT recommended due to rapid emergence of resistance and high treatment failure rates 3. This is particularly critical in:
- Implant-related infections: Fluoroquinolones should only be used in combination with rifampin for staphylococcal infections when implants are retained 3
- Fracture-related infections: Levofloxacin monotherapy has demonstrated high failure rates 3
- Prosthetic joint infections: Combination therapy with rifampin is required for staphylococcal infections 3
When Levofloxacin IS Appropriate for Staph
Skin and Soft Tissue Infections
For uncomplicated MSSA skin infections, levofloxacin 500 mg PO once daily for 7-10 days is effective 1, 4. For complicated skin infections, levofloxacin 750 mg IV/PO once daily for 7-14 days can be used 1, 3.
Community-Acquired Pneumonia
For MSSA community-acquired pneumonia, levofloxacin 750 mg IV/PO once daily for 5-7 days is an alternative to first-line beta-lactams 2, 1. The 750 mg dose is preferred over 500 mg for pneumonia 2.
Necrotizing Fasciitis
Levofloxacin 750 mg IV every 24 hours plus metronidazole 500 mg every 8 hours IV is listed as a combination regimen option for necrotizing infections involving the axilla or perineum 3.
Microbiological Activity
Research demonstrates that levofloxacin has potent bactericidal activity against MSSA 5, 6, 7:
- Bactericidal activity occurs within 3 hours against staphylococci 5
- Superior serum bactericidal activity compared to ofloxacin against both MSSA and MRSA (when susceptible) 6
- In experimental endocarditis models, levofloxacin was at least equivalent to flucloxacillin or vancomycin for MSSA 7
- Importantly, levofloxacin has a lower propensity to select for resistance compared to ciprofloxacin 7
Common Pitfalls to Avoid
Never use levofloxacin for MRSA - this is a critical error that will lead to treatment failure 2
Never use as monotherapy for implant-related staphylococcal infections - always combine with rifampin after debridement when implants are retained 3
Do not start fluoroquinolones before debridement in implant infections - wait until wounds are dry to avoid superinfection with resistant organisms 3
Avoid in high bacterial load situations without combination therapy - resistance emerges rapidly 3
Monitor for fluoroquinolone toxicity including tendinopathy and QTc prolongation 3
Preferred Alternatives for Staphylococcal Infections
For most staphylococcal infections, beta-lactams remain first-line 3, 8:
- MSSA: Cloxacillin, dicloxacillin, cefazolin, or cephalexin 3, 8
- MRSA: Vancomycin, linezolid, or daptomycin 3, 8
Levofloxacin should be considered an alternative agent when beta-lactams cannot be used or in specific combination regimens 3.