Treatment Duration for Skin Abscesses
For skin abscesses, a 5-10 day course of antibiotics is recommended after incision and drainage when antibiotic therapy is indicated. 1
When Antibiotics Are Needed
Not all skin abscesses require antibiotics. Incision and drainage alone is often sufficient for simple, uncomplicated abscesses. However, antibiotics should be added in the following situations:
- Abscess with surrounding cellulitis
- Systemic signs of infection (fever >38.5°C, heart rate >110 beats/minute)
- Erythema extending >5 cm beyond wound margins
- Immunocompromised patients
- Multiple sites of infection
- Inadequate response to drainage alone
- Abscess in an area difficult to drain completely
Antibiotic Selection
When antibiotics are indicated, selection should be based on likely pathogens:
First-line options for MRSA coverage (common in skin abscesses):
- Trimethoprim-sulfamethoxazole (1-2 double-strength tablets twice daily)
- Clindamycin (300-450 mg four times daily)
- Doxycycline (100 mg twice daily) - not for children <8 years
For MSSA coverage:
- Cephalexin (500 mg four times daily)
- Dicloxacillin (500 mg four times daily)
Evidence for Treatment Duration
Recent high-quality evidence supports the following approach:
- Standard duration: 5-10 days 1
- The Infectious Diseases Society of America (IDSA) recommends treating recurrent abscesses with a 5-10 day course of antibiotics active against the isolated pathogen 1
- For neutropenic patients with SSTIs, the IDSA recommends 7-14 days of treatment 1
Special Considerations
Recurrent abscesses: For patients with recurrent abscesses, consider a 5-day decolonization regimen consisting of:
- Intranasal mupirocin twice daily
- Daily chlorhexidine washes
- Daily decontamination of personal items (towels, sheets, clothes) 1
Treatment failure: If infection has not improved after 5 days, treatment should be extended 1
Pediatric patients: Adjust dosing by weight and avoid doxycycline in children under 8 years
Evidence on Antibiotic Efficacy
Recent randomized controlled trials have demonstrated that antibiotics improve outcomes for drained skin abscesses:
A 2017 study showed that both clindamycin and trimethoprim-sulfamethoxazole for 10 days improved cure rates compared to placebo (83.1% and 81.7% vs 68.9%, respectively) 2
A 2016 trial demonstrated that trimethoprim-sulfamethoxazole for 7 days resulted in higher cure rates than placebo (92.9% vs 85.7%) 3
These benefits were observed regardless of abscess size or presence of guideline-recommended antibiotic indications 4
Common Pitfalls to Avoid
- Undertreating: Not extending antibiotic duration when infection fails to improve within 5 days
- Overtreating: Using antibiotics for all abscesses regardless of size or complexity
- Inappropriate antibiotic selection: Not considering local MRSA prevalence when selecting empiric therapy
- Neglecting drainage: Relying solely on antibiotics without adequate incision and drainage
- Missing recurrence factors: Not addressing underlying causes of recurrent abscesses
By following these evidence-based guidelines, clinicians can optimize treatment outcomes while practicing good antibiotic stewardship.