What is the recommended treatment for ringworm (tinea infection)?

Treatment of Ringworm (Tinea Infection)

For ringworm (tinea) infections, oral therapy with griseofulvin or terbinafine is recommended as first-line treatment, with the specific agent chosen based on the causative organism. 1, 2

Diagnosis

• Accurate diagnosis is essential before starting treatment - identification should be made either by direct microscopic examination of infected tissue in potassium hydroxide solution or by culture on appropriate medium 2
• In high-risk populations or when clinical features are highly suggestive (scaling, lymphadenopathy, alopecia), treatment may be initiated before culture results are available 1

Treatment Approach

Topical Therapy

• Topical therapy alone is not recommended for tinea capitis (scalp ringworm) 1
• For tinea corporis (body), tinea cruris (groin), and tinea pedis (feet), topical antifungal agents are often effective as first-line treatment 3, 4
• Common topical agents include:
  • Azoles (clotrimazole, miconazole)
  • Allylamines (terbinafine, naftifine)
  • Treatment duration: 2 weeks for tinea corporis/cruris, 4 weeks for tinea pedis 4

Oral Therapy

For Tinea Capitis:

1. Griseofulvin:

   • First-line treatment for Microsporum species infections 1
   • Dosage:
     • Children: 10-20 mg/kg/day for 6-8 weeks
     • Adults: 500 mg daily (can start with 0.75-1.0 g/day for widespread lesions) 2
   • Only licensed product for tinea capitis in children in the UK 1

2. Terbinafine:

   • First-line for Trichophyton species infections 1
   • Dosage based on weight:
     • <20 kg: 62.5 mg daily
     • 20-40 kg: 125 mg daily

     • 40 kg: 250 mg daily

   • Treatment duration: 2-4 weeks 1

For Extensive Tinea Corporis/Cruris:

• Oral therapy is indicated when infection is widespread or adjacent to eyes, ears, or mouth 5
• Options include:
  • Fluconazole: 50-100 mg daily or 150 mg once weekly for 2-3 weeks 6
  • Itraconazole: 100 mg daily for 2 weeks or 200 mg daily for 7 days 6
  • Terbinafine: 250 mg daily for 1-2 weeks 6

Treatment Selection Algorithm

1. Identify the type of tinea infection:

   • Tinea capitis (scalp) - requires oral therapy
   • Tinea corporis/cruris/pedis - topical therapy for limited disease, oral for extensive disease

2. For tinea capitis:

   • If Microsporum species or unknown: Griseofulvin for 6-8 weeks
   • If Trichophyton species: Terbinafine for 2-4 weeks

3. For tinea corporis/cruris/pedis:

   • Limited disease: Topical azole or allylamine
   • Extensive disease: Oral therapy as outlined above

Adjunctive Measures

• For tinea capitis, topical antifungal shampoos (ketoconazole 2%, selenium sulfide 1%) can help reduce transmission of spores 1
• General hygiene measures should be observed to control sources of infection or reinfection 2
• For tinea capitis due to T. tonsurans, screening of family members and close contacts is warranted 1

Treatment Failure Considerations

• Ensure correct diagnosis was made initially
• Consider lack of compliance, suboptimal absorption, or relative insensitivity of the organism 1
• For clinical improvement but ongoing positive mycology, continue current therapy for 2-4 more weeks 1
• If no clinical improvement, switch to second-line therapy:
  • If initial treatment was griseofulvin, switch to terbinafine for Trichophyton infections
  • If initial treatment was terbinafine, switch to griseofulvin for Microsporum infections
  • Itraconazole (5 mg/kg/day for 2-4 weeks) can be used as an alternative 1

Important Caveats

• Treatment should continue until the infecting organism is completely eradicated as indicated by appropriate clinical or laboratory examination 2
• Clinical relapse will occur if medication is not continued until the organism is eradicated 2
• Oral antifungal drugs are not effective against bacterial infections, candidiasis, or other non-dermatophyte fungal infections 2
• The use of systemic antifungals is not justified for minor or trivial dermatophyte infections that will respond to topical agents alone 2