What is the treatment for a fungal skin infection?

Treatment for Fungal Skin Infections

For most superficial fungal skin infections, topical antifungal agents are the first-line treatment, with systemic therapy reserved for extensive disease, nail infections, scalp infections, or treatment failures. 1

Treatment by Infection Type

Candidal Skin Infections (Intertrigo)

• Topical azoles (clotrimazole, miconazole) or polyenes (nystatin) are effective first-line treatments for candidal skin infections, particularly in skin folds of obese and diabetic patients 2, 1
• Keeping the infected area dry is essential for treatment success—failure to do this is a common pitfall that undermines therapy 2, 1
• Treatment duration typically ranges from 1-2 weeks with topical agents 3

Candidal Paronychia

• Drainage is the most critical intervention, followed by topical antifungal therapy 2, 1

Dermatophyte Infections (Tinea Corporis, Tinea Cruris, Tinea Pedis)

Topical therapy:

• Fungicidal agents (allylamines: terbinafine, naftifine, butenafine) are preferred over fungistatic agents (azoles) because they kill fungi rather than just inhibiting growth 3
• Allylamines achieve high cure rates with treatment as short as once daily for 1 week 3
• This is clinically important because patients often stop treatment when skin appears healed (typically after 1 week)—fungi recur more frequently with fungistatic drugs if treatment is stopped early 3
• Azoles (miconazole, clotrimazole, ketoconazole) remain effective alternatives, particularly for mixed infections or yeast involvement 3, 4

Systemic therapy (for extensive or resistant cases):

• Terbinafine 250 mg daily for 1-2 weeks 5
• Itraconazole 100 mg daily for 2 weeks or 200 mg daily for 7 days 5
• Fluconazole 50-100 mg daily or 150 mg once weekly for 2-3 weeks 5

Tinea Capitis (Scalp Ringworm)

• Oral therapy is required—topical agents alone are ineffective 2, 1
• Griseofulvin remains the only licensed treatment for children in the UK: 20 mg/kg daily for 6-8 weeks, taken with fatty food to improve absorption 2
• Treatment should ideally await fungal confirmation, but in high-risk populations with typical features (scaling, lymphadenopathy, alopecia) or kerion, start therapy immediately 2
• Add topical antifungal shampoos (ketoconazole 2%, selenium sulfide 1%, or povidone-iodine) to reduce spore transmission, though these alone are insufficient for cure 2

Onychomycosis (Nail Infections)

• Topical agents are ineffective for nail infections—oral therapy is required 1
• For dermatophyte nail infections: terbinafine or itraconazole are preferred over griseofulvin 1
• For Candida onychomycosis: azoles are preferred because terbinafine has limited activity against yeasts 1
• Treatment duration is prolonged (typically 6-12 weeks or longer) due to slow nail growth 4

Pityriasis Versicolor

Topical therapy (first-line):

• Topical azoles or selenium sulfide for localized disease 4

Systemic therapy (for extensive disease):

• Itraconazole 200 mg daily for 5-7 days 5, 4
• Fluconazole 400 mg as a single dose 5, 4
• Note: Terbinafine is ineffective for pityriasis versicolor 5

Critical Pitfalls to Avoid

• Do not use topical therapy alone for tinea capitis or onychomycosis—these require systemic treatment 2, 1
• Do not prescribe terbinafine for yeast infections (Candida or pityriasis versicolor)—it lacks adequate activity against yeasts 1, 5
• Ensure the infected area stays dry, especially for intertrigo—moisture undermines treatment efficacy 2, 1
• Be aware of emerging terbinafine resistance in Trichophyton mentagrophytes ITS genotype VIII (T. indotineae)—if treatment fails, consider resistance testing and switch to itraconazole 4
• Patients often stop treatment when skin appears healed (typically after 1 week)—this is why fungicidal agents (allylamines) are preferred over fungistatic agents (azoles) for dermatophyte infections 3

Special Considerations

• For widespread infections, hair follicle involvement, or treatment failures, systemic therapy is necessary 3
• Cost considerations may influence choice, especially for large body surface areas—generic topical agents are generally effective regardless of mechanism 3
• Always combine oral antifungal treatment with topical therapy for optimal outcomes 4