What is the treatment for ringworm?

Treatment of Ringworm (Tinea Corporis)

For uncomplicated ringworm of the body, topical antifungal therapy with azoles (clotrimazole 1% or miconazole 2%) applied twice daily for 2-4 weeks is the first-line treatment, with oral therapy reserved for extensive, resistant, or hair-bearing area infections. 1

Topical Therapy (First-Line for Localized Disease)

Topical antifungals are highly effective for most cases of tinea corporis and should be continued for at least one week after clinical clearing. 2

Preferred Topical Agents:

• Clotrimazole 1% cream applied twice daily for 2-4 weeks 1, 3
• Miconazole 2% cream applied twice daily for 2-4 weeks 1
• Terbinafine cream applied once or twice daily for 1-2 weeks (shorter duration than azoles) 2, 3
• Naftifine 1% cream applied once or twice daily 3

Evidence Supporting Topical Therapy:

• Terbinafine demonstrates significantly higher clinical cure rates compared to placebo (RR 4.51, NNT 3) 3
• Naftifine shows superior mycological cure rates versus placebo (RR 2.38, NNT 3) 3
• Clotrimazole achieves better mycological cure than placebo (RR 2.87, NNT 2) 3
• Allylamines (terbinafine, naftifine) require shorter treatment duration (1-2 weeks) compared to azoles (2-4 weeks) 2, 4

Oral Therapy (For Extensive or Resistant Disease)

Oral antifungals are indicated when topical therapy fails after 2 weeks, when infection is extensive, or when hair-bearing areas are involved. 1, 5, 6

Preferred Oral Agents:

Griseofulvin (FDA-approved for dermatophyte infections):

• Adults: 500 mg daily (can give as 125 mg four times daily, 250 mg twice daily, or 500 mg once daily) for 2-4 weeks 5
• Children >2 years: 10 mg/kg/day (30-50 lbs: 125-250 mg daily; >50 lbs: 250-500 mg daily) 5
• Treatment duration for tinea corporis: 2-4 weeks 5
• Must continue until organism is completely eradicated to prevent clinical relapse 5

Alternative Oral Agents:

• Fluconazole: 150-200 mg weekly for 2-4 weeks for extensive or resistant cases 1, 4
• Itraconazole: 100 mg daily for 2 weeks OR 200 mg daily for 7 days 4
• Terbinafine: 250 mg daily for 1-2 weeks 4

When to Use Oral Therapy:

• Extensive body surface area involvement 5, 6
• Failure to respond to appropriate topical therapy after 2 weeks 1
• Infection of hair-bearing areas (tinea capitis requires oral therapy) 6, 7
• Patient preference or compliance issues with topical application 6

Treatment Duration and Monitoring

Treatment must continue for at least one week after clinical clearing to prevent relapse. 2

• Tinea corporis with topical therapy: 2-4 weeks total 2, 3
• Tinea corporis with oral therapy: 2-4 weeks 5, 4
• If no improvement after 2 weeks of appropriate therapy: Switch to a different class of antifungal 1

Diagnostic Confirmation

Accurate diagnosis with KOH preparation or fungal culture is essential before initiating therapy, particularly for oral antifungals. 5, 2

• Direct microscopy with potassium hydroxide (KOH) preparation provides rapid confirmation 2
• Fungal culture identifies specific dermatophyte species 5
• Clinical diagnosis alone is acceptable for initiating topical therapy in typical presentations 2

Adjunctive Measures

Address predisposing factors and sources of reinfection to prevent treatment failure. 5, 6

• Control skin moisture and improve hygiene 5
• Investigate and treat other body sites of infection 6
• Identify and treat sources of infection (pets, family members) 6
• Consider topical antifungal powder or spray for prevention after cure 5

Common Pitfalls to Avoid

• Do not stop treatment when lesions appear clinically clear - continue for at least one additional week to ensure complete eradication 5, 2
• Do not use griseofulvin for Candida infections - it is only effective against dermatophytes 5
• Do not use topical therapy alone for tinea capitis - scalp infections require oral therapy 6, 7
• Do not use combination steroid-antifungal creams as first-line - while they may provide faster symptom relief, they are not recommended in guidelines and should be reserved for cases with significant inflammation 3
• Avoid premature discontinuation of oral therapy - this leads to clinical relapse 5

Special Considerations for Inflammation

When significant inflammation is present, consider an agent with inherent anti-inflammatory properties or short-term use of combination antifungal/steroid preparations, though use with caution. 2

• Combination products show higher clinical cure rates at end of treatment but similar mycological cure rates compared to antifungals alone 3
• Risk of skin atrophy and steroid-related complications with prolonged use 2
• Not recommended as first-line therapy in current guidelines 3