What is the recommended antibiotic treatment for a skin infection with no drainage?

Antibiotic Treatment for Skin Infections Without Drainage

For skin infections without drainage (cellulitis), amoxicillin-clavulanate is the recommended first-line antibiotic treatment due to its activity against both aerobic and anaerobic bacteria. 1

Antibiotic Selection Algorithm

First-line Options:

• Amoxicillin-clavulanate (875/125 mg twice daily orally for 5-6 days) 2
• Cephalexin (500 mg 3-4 times daily for 5-6 days) 2
  • Particularly effective for streptococcal and methicillin-susceptible Staphylococcus aureus infections
  • Achieves cure rates of 90% or higher for these pathogens 3

For patients with penicillin allergy:

• Clindamycin (300-450 mg orally three times daily for 5-6 days) 2

For suspected or confirmed MRSA:

• Consider MRSA coverage if risk factors present:
  • Prior MRSA infection
  • Nasal colonization with MRSA
  • Injection drug use
  • Athletes, prisoners, military recruits
  • Residents of long-term care facilities 2
• Options for MRSA coverage:
  • Trimethoprim-sulfamethoxazole
  • Doxycycline
  • Clindamycin (if local resistance rates are low)
  • Linezolid (600 mg orally twice daily) for severe infections 4

Treatment Duration

• Standard duration: 5-6 days 2
• Extend treatment if infection has not improved within this period
• For more severe infections, treatment may need to be extended to 10-14 days 2

Inpatient Treatment for Severe Infections

For severe non-purulent infections requiring IV therapy:

• Vancomycin plus either piperacillin-tazobactam, ampicillin-sulbactam, or a carbapenem 1
• Consider hospitalization for patients with:
  • Systemic inflammatory response syndrome
  • Altered mental status
  • Hemodynamic instability
  • Concern for deeper infection
  • Immunocompromise
  • Failure of outpatient treatment 2

Supportive Care

• Elevate the affected area to reduce edema
• Treat predisposing factors such as edema, obesity, eczema, and venous insufficiency
• For lower-extremity cellulitis, examine interdigital toe spaces and treat any fissuring, scaling, or maceration 2

Monitoring and Follow-up

• Daily monitoring for the first 48-72 hours is recommended to ensure response to antibiotics
• If no improvement within 72 hours, consider:
  • Changing antibiotics
  • Surgical consultation
  • Reassessment for deeper infection 2

Common Pitfalls to Avoid

1. Failure to consider MRSA: In areas with high MRSA prevalence, empiric coverage may be necessary
2. Inadequate duration: Ensure a full 5-day course at minimum, with extension if needed
3. Missing underlying conditions: Treat predisposing factors to prevent recurrence
4. Delayed recognition of necrotizing infection: Watch for signs of deeper infection requiring surgical intervention
5. Overuse of broad-spectrum antibiotics: Reserve MRSA coverage for specific risk factors to prevent antimicrobial resistance

Remember that while drainage is the primary treatment for purulent infections, non-purulent infections like cellulitis require appropriate antibiotic therapy as outlined above.