What is the treatment for fungal skin infection?

Treatment of Fungal Skin Infections

The first-line treatment for most fungal skin infections is a topical antifungal agent, specifically an azole (clotrimazole, miconazole) or allylamine (terbinafine), applied 2-3 times daily for 1-2 weeks. 1

Types of Fungal Skin Infections and Their Treatment

Superficial Dermatophyte Infections (Tinea)

• Tinea corporis/cruris (ringworm/jock itch)

  • First-line: Topical azoles (clotrimazole, miconazole) or allylamines (terbinafine) applied 2-3 times daily for 1-2 weeks 1, 2
  • For extensive disease: Oral therapy with fluconazole (150 mg once weekly for 2-3 weeks), itraconazole (100 mg daily for 2 weeks), or terbinafine (250 mg daily for 1-2 weeks) 3

• Tinea pedis (athlete's foot)

  • First-line: Topical azoles or allylamines for 2-4 weeks 2
  • For resistant cases: Oral fluconazole (150 mg weekly), itraconazole (100 mg daily for 2 weeks), or terbinafine (250 mg daily for 2 weeks) 3

• Tinea capitis (scalp ringworm)

  • Requires oral therapy: Griseofulvin (20-25 mg/kg/day for 6-8 weeks) 4
  • For Trichophyton species: Terbinafine may be more effective 4
  • For Microsporum species: Griseofulvin is preferred 4
  • Adjunctive therapy: Antifungal shampoo (ketoconazole 2% or selenium sulfide 1%) to reduce transmission 4

Candida Infections

• Candida intertrigo (skin fold infections)

  • First-line: Topical azoles (clotrimazole, miconazole) or nystatin applied 2-3 times daily for 1-2 weeks 1
  • Critical: Keep affected areas clean and dry 1

• Vulvovaginal candidiasis

  • Uncomplicated: Single dose fluconazole 150 mg orally 4, 5
  • Complicated/recurrent: Fluconazole 150 mg every 72 hours for 3 doses, followed by weekly fluconazole 150 mg for 6 months for recurrent cases 4
  • For non-albicans species: Consider topical boric acid (600 mg daily for 14 days) 4

Other Fungal Infections

• Pityriasis versicolor (Malassezia)

  • Topical: Selenium sulfide 2.5% shampoo, ketoconazole 2% shampoo, or topical azoles 6
  • Oral: Single dose fluconazole 400 mg or itraconazole 200 mg daily for 5-7 days 3

• Aspergillus skin infections (rare, usually in immunocompromised)

  • Voriconazole is the treatment of choice 4
  • Surgical debridement may be necessary 4

Treatment Selection Considerations

Topical vs. Oral Therapy

• Use topical therapy for:

  • Localized infections
  • Limited body surface area involvement
  • Immunocompetent patients
  • First episodes

• Consider oral therapy for:

  • Extensive disease
  • Hair or nail involvement
  • Failure of topical therapy
  • Immunocompromised patients
  • Recurrent infections

Medication Selection

• Azoles (clotrimazole, miconazole): Fungistatic, good for yeasts and dermatophytes 2
• Allylamines (terbinafine): Fungicidal, excellent for dermatophytes, less effective for Candida 2
• Polyenes (nystatin): Primarily for Candida infections 7

Special Populations

Immunocompromised Patients

• Lower threshold for systemic therapy 4
• Consider broader spectrum agents 4
• Longer treatment duration may be necessary 4
• Blood cultures and skin biopsies should be obtained for suspicious lesions 4

Pediatric Patients

• Adjust dosing based on weight 5
• For tinea capitis: Oral therapy is required; griseofulvin remains first-line 4

Treatment Pitfalls and Caveats

1. Inadequate treatment duration is a common cause of recurrence - continue treatment until complete resolution plus additional days (usually 1-2 weeks total) 1

2. Failure to keep affected areas dry can lead to treatment failure, especially for intertrigo 1

3. Misdiagnosis - confirm diagnosis with KOH preparation or culture when possible 4

4. Drug interactions - azoles can interact with many medications; check for interactions before prescribing systemic therapy 7

5. Resistance development - more common with prolonged or repeated courses of antifungal therapy 4

6. Treatment failure may indicate:

   • Wrong diagnosis
   • Non-compliance
   • Reinfection from fomites or contacts
   • Need for longer treatment duration
   • Need for systemic rather than topical therapy

By selecting the appropriate antifungal agent based on the type of infection and patient factors, most fungal skin infections can be effectively treated with minimal side effects and good clinical outcomes.