What is the recommended treatment for a superficial facial skin infection such as impetigo or folliculitis in an otherwise healthy adult?

Treatment for Superficial Facial Skin Infection

For a superficial facial skin infection such as impetigo or folliculitis in an otherwise healthy adult, prescribe a 7-day course of oral dicloxacillin or cephalexin as first-line therapy, switching to clindamycin, doxycycline, or trimethoprim-sulfamethoxazole if MRSA is suspected or confirmed. 1

Initial Assessment

Before initiating treatment, evaluate the following:

• Obtain Gram stain and culture from any purulent drainage or exudate to guide definitive antibiotic selection 1
• Assess for systemic signs of infection: fever >38°C, tachycardia (>90 bpm), tachypnea (>24 breaths/min), or abnormal white blood cell count (<4,000 or >12,000 cells/µL) 1
• Determine infection characteristics: purulent versus non-purulent, extent of erythema, presence of bullae or crusting 1

First-Line Antibiotic Therapy

For Methicillin-Susceptible S. aureus (Expected in Most Cases)

• Dicloxacillin or cephalexin orally for 7 days is the recommended regimen, as S. aureus isolates from impetigo are usually methicillin-susceptible 1
• If cultures yield streptococci alone, oral penicillin is the preferred agent 1

For Suspected or Confirmed MRSA

• Switch to MRSA-active oral agents: clindamycin, doxycycline, or trimethoprim-sulfamethoxazole for 7 days 1
• MRSA should be suspected in areas with high community prevalence or if the patient has risk factors for resistant organisms 1

Topical Therapy Considerations

• Topical mupirocin ointment 2% is FDA-approved for impetigo caused by S. aureus and S. pyogenes and may be used for localized, non-widespread lesions 2
• Topical therapy alone is insufficient for more extensive infections, folliculitis with systemic signs, or any surgical site infection—systemic antibiotics are required 3

Management Algorithm by Infection Type

Impetigo (Non-Bullous or Bullous)

• Localized disease: Topical mupirocin may suffice if lesions are limited 2, 4
• Widespread or severe disease: Oral dicloxacillin or cephalexin for 7 days 1
• Debride crusts before applying topical therapy to improve penetration 4

Folliculitis

• Superficial folliculitis: May respond to topical antibiotics if mild 4, 5
• Deeper or extensive folliculitis: Requires oral anti-staphylococcal antibiotics (dicloxacillin, cephalexin) for 7 days 6, 5
• If purulent collection develops (furuncle), incision and drainage may be necessary in addition to antibiotics 1

When to Escalate Therapy

Reassess at 48-72 hours for clinical response:

• No improvement: Consider MRSA coverage if not already initiated, or evaluate for alternative diagnosis 3
• Systemic signs develop: Initiate IV antibiotics (vancomycin or cefazolin) and consider hospitalization 1
• Extension beyond initial borders: May indicate cellulitis requiring broader coverage and longer treatment duration 1, 5

Critical Pitfalls to Avoid

• Do not use trimethoprim-sulfamethoxazole monotherapy unless streptococcal infection is definitively ruled out by culture, as it lacks adequate streptococcal coverage 3
• Do not add rifampin as adjunctive therapy—it is not recommended for skin and soft tissue infections 3
• Do not rely on topical antibiotics alone for extensive impetigo, folliculitis with systemic signs, or any infection at a surgical site 3
• Do not use fluoroquinolones as first-line therapy, as they are inadequate for MRSA and not preferred for uncomplicated facial infections 1, 7

Duration and Follow-Up

• Complete the full 7-day course even if symptoms improve rapidly to prevent recurrence and resistance 1, 3
• Culture results should guide any necessary antibiotic adjustment or de-escalation 3
• During outbreaks of post-streptococcal glomerulonephritis, systemic antimicrobials are mandatory to eliminate nephritogenic strains from the community 1