Augmentin for Oxacillin-Susceptible Staphylococcus Wound Infections
Yes, Augmentin (amoxicillin-clavulanate) is an acceptable and guideline-supported option for treating wound infections caused by oxacillin-susceptible Staphylococcus species, though it is not the first-line choice.
First-Line Agents Are Preferred
For oxacillin-susceptible Staphylococcus aureus (MSSA) wound infections, the preferred first-line antibiotics are the anti-staphylococcal penicillins (dicloxacillin, cloxacillin, oxacillin) or first-generation cephalosporins (cephalexin, cefazolin) 1, 2. These agents provide more targeted coverage and are specifically recommended by the Infectious Diseases Society of America 1.
Augmentin as an Alternative
However, amoxicillin-clavulanate is explicitly listed as an acceptable alternative in multiple IDSA guidelines:
- For impetigo and minor skin infections, oral amoxicillin-clavulanate is recommended alongside dicloxacillin and cephalexin 1
- For diabetic foot infections with mild to moderate severity, amoxicillin-clavulanate is listed as an appropriate option 1
- For animal and human bite wounds, amoxicillin-clavulanate is the preferred oral agent 1
Clinical Rationale
The key advantage of Augmentin is that the clavulanate component protects amoxicillin from beta-lactamase degradation 3. While oxacillin susceptibility indicates the organism does not produce the chromosomal mecA-mediated resistance, some strains may still produce plasmid-mediated beta-lactamases that could inactivate amoxicillin alone 4.
In a mouse model of mixed wound infection, amoxicillin alone failed to eliminate Streptococcus pyogenes when beta-lactamase-producing S. aureus was present, whereas amoxicillin-clavulanate successfully controlled the infection 3. This demonstrates the clinical relevance of beta-lactamase inhibition even with susceptible organisms.
When to Use Augmentin
Augmentin is particularly appropriate when:
- First-line agents are contraindicated (e.g., penicillin allergy that is not anaphylactic) 1
- Mixed infection is suspected with potential beta-lactamase producers or gram-negative organisms 3
- Broader coverage is desired for polymicrobial wound infections 1
- Patient convenience requires a single agent rather than combination therapy 1
Treatment Duration
For uncomplicated skin and soft tissue infections, treat for 5-10 days based on clinical response 1. More severe infections may require 7-14 days 1.
Important Caveats
- Ensure true oxacillin susceptibility through proper culture and sensitivity testing before relying on Augmentin 1
- If MRSA is suspected or confirmed, Augmentin is ineffective and agents like trimethoprim-sulfamethoxazole, doxycycline, clindamycin, or vancomycin should be used instead 1, 2
- Surgical drainage remains critical for purulent infections and should be performed whenever feasible 1, 2