What is the recommended treatment for ringworm?

Treatment of Ringworm (Tinea Corporis)

For uncomplicated ringworm of the body, apply topical clotrimazole 1% or miconazole 2% cream twice daily for 2-4 weeks as first-line therapy. 1, 2

Topical Therapy for Localized Infection

First-line topical agents:

• Clotrimazole 1% cream applied twice daily for 2-4 weeks is highly effective for ringworm 1
• Miconazole 2% cream applied twice daily for 2-4 weeks provides equivalent efficacy 1
• Terbinafine cream demonstrates superior efficacy compared to placebo (RR 4.51, NNT 3) and requires only 1-2 weeks of treatment 3
• Naftifine 1% cream shows strong mycological cure rates (RR 2.38, NNT 3) 3

The evidence from a large Cochrane review demonstrates that while all topical antifungals are effective, allylamines (terbinafine, naftifine) offer the advantage of shorter treatment duration (1-2 weeks) compared to azoles (2-4 weeks) 4, 3. No single agent has proven superiority over others for superficial dermatophyte infections 2.

Oral Therapy for Extensive or Resistant Cases

When to escalate to systemic treatment:

• Extensive body surface area involvement (widespread lesions) 5, 6
• Failure of topical therapy after 2-4 weeks 2
• Hyperkeratotic lesions unresponsive to topical monotherapy 6
• Infection in areas difficult to treat topically (complex skin folds) 6

Oral treatment options:

• Griseofulvin 500 mg daily (or 10 mg/kg/day in children) for 2-4 weeks is FDA-approved for tinea corporis 5, 7
• Terbinafine 250 mg daily for 1-2 weeks provides effective cure with shorter duration 8
• Fluconazole 150-200 mg weekly for 2-4 weeks is recommended for extensive or resistant cases 1, 8
• Itraconazole 100 mg daily for 2 weeks or 200 mg daily for 7 days offers alternative dosing flexibility 8

The FDA label for griseofulvin specifies that treatment must continue until the infecting organism is completely eradicated, with typical duration for tinea corporis being 2-4 weeks 5. However, newer agents like terbinafine and fluconazole offer shorter treatment courses with similar efficacy 8.

Critical Adjunctive Measures

Essential non-pharmacologic interventions:

• Keep infected areas dry throughout treatment, as moisture promotes fungal growth 2
• Address predisposing factors including diabetes, immunosuppression, or excessive moisture to prevent recurrence 2
• Implement general hygiene measures to control sources of infection or reinfection 5
• Continue treatment for at least one week after clinical clearing to prevent relapse 4

When to Switch Therapy

If no improvement after 2 weeks of appropriate topical therapy, switch to a different class of antifungal agent or escalate to oral therapy 1, 2. This is particularly important as clinical relapse will occur if medication is discontinued before complete eradication of the organism 5.

Common Pitfalls to Avoid

• Do not use topical steroids alone, as they can worsen dermatophyte infections 4
• Avoid combination antifungal/steroid preparations as first-line therapy, though they may show higher initial clinical cure rates, they carry risks of skin atrophy and are not recommended in clinical guidelines 3
• Do not discontinue treatment based solely on clinical appearance; continue until mycological cure is confirmed 5, 4
• Confirm diagnosis with KOH preparation or fungal culture before initiating treatment, as accurate identification of dermatophytes is essential 5