What is the treatment for ringworm (tinea infection)?

Treatment for Ringworm (Tinea Infection)

For tinea corporis (body) and tinea cruris (groin), use topical terbinafine or topical naftifine as first-line therapy, applied once or twice daily for 1-2 weeks; for tinea capitis (scalp), oral terbinafine is the preferred treatment at weight-based dosing for 2-4 weeks. 1, 2

Topical Treatment for Tinea Corporis and Tinea Cruris

First-Line Topical Agents

• Terbinafine 1% cream is highly effective, achieving clinical cure rates 4.5 times higher than placebo (NNT 3), applied once or twice daily for 1-2 weeks 3, 1

• Naftifine 1% cream demonstrates strong efficacy with mycological cure rates 2.4 times higher than placebo (NNT 3), applied once or twice daily for 1-2 weeks 3

• Azole antifungals (clotrimazole, miconazole, ketoconazole) are effective alternatives with mycological cure rates 2.9 times higher than placebo for clotrimazole (NNT 2), typically applied twice daily for 2-4 weeks 3

Treatment Duration and Application

• Most topical treatments require 2-4 weeks of application, though terbinafine and naftifine may achieve cure with shorter courses of 1-2 weeks 3, 2

• Continue treatment for at least one week after clinical symptoms resolve to ensure mycological cure 2

Oral Treatment for Extensive or Resistant Disease

Indications for Oral Therapy

• Tinea capitis (scalp ringworm) always requires oral treatment because topical agents cannot penetrate hair follicles adequately 4, 2, 5

• Extensive tinea corporis or cruris involving large body surface areas 2

• Lack of response to topical treatment after 2-4 weeks 2

• Immunocompromised patients 2

• Hair follicle involvement (Majocchi's granuloma) 2

Oral Terbinafine (First-Line for Tinea Capitis)

• Dosing by weight for children and adults:

  • <20 kg: 62.5 mg daily
  • 20-40 kg: 125 mg daily

  • 40 kg: 250 mg daily 4

• Treatment duration: 2-4 weeks for tinea capitis caused by Trichophyton species 4, 2

• Terbinafine is preferred over griseofulvin because it is well-tolerated, effective, and requires shorter treatment duration 2, 4

Alternative Oral Agents

• Griseofulvin remains an option, particularly for Microsporum species, dosed at:

  • 10-20 mg/kg/day for children
  • Treatment duration: 6-8 weeks 4

• Itraconazole 5 mg/kg/day for 2-4 weeks or pulse dosing (100 mg daily for 4 weeks) is effective for both Trichophyton and Microsporum species 4

• Fluconazole 6 mg/kg once weekly has been used but offers no cost advantage and has more side effects 4

Critical Management Considerations

Avoid Combination Antifungal-Corticosteroid Products

• Do not use topical steroid-antifungal combinations as routine first-line therapy, despite slightly higher initial clinical cure rates, because steroids may suppress local immune response and allow deeper fungal invasion 6, 2

• If combination products are used for heavily inflamed lesions, limit use to 2 weeks maximum and only in adults, never in children under 12 years or on facial/occluded areas 6

Confirm Diagnosis Before Treatment

• Clinical diagnosis alone is unreliable—tinea corporis mimics eczema, and onychomycosis mimics psoriatic or traumatic nail dystrophy 2, 4

• Obtain KOH preparation or fungal culture to confirm dermatophyte infection before initiating prolonged oral therapy 2, 4

Treatment Failure Management

• If no clinical improvement after 2-4 weeks of appropriate topical therapy, switch to oral antifungals 2

• For tinea capitis with treatment failure on terbinafine, switch to itraconazole or griseofulvin (particularly for Microsporum species) 4

• Consider emerging resistant tinea infections if standard treatments fail—these may require prolonged oral therapy and specialized testing 2

Adjunctive Measures for Tinea Capitis

• Children receiving appropriate oral therapy should attend school or nursery without restriction 4

• Screen and treat all family members and close contacts for Trichophyton tonsurans infections 4

• Continue treatment until mycological clearance is achieved, not just clinical improvement 4

Special Populations

Pediatric Considerations

• Oral terbinafine is safe and effective in children at weight-based dosing 4, 2

• Avoid topical steroid-antifungal combinations in children under 12 years due to increased risk of cutaneous adverse effects 6

Monitoring Requirements

• Baseline liver function tests and complete blood count are recommended before starting oral terbinafine in adults with history of hepatotoxicity or hematological abnormalities 4

• Monitor liver function during prolonged oral therapy (>1 month) 4