Treatment of Tinea (Ringworm)
For tinea corporis and tinea cruris, topical terbinafine 1% cream applied once daily for 1 week is the first-line treatment, while tinea capitis requires oral antifungal therapy with agent selection based on the causative organism. 1, 2
Tinea Corporis and Tinea Cruris (Body and Groin)
First-Line Topical Treatment
- Terbinafine 1% cream once daily for 1 week is the preferred first-line treatment for localized tinea corporis and tinea cruris, offering the shortest treatment duration with high efficacy 1, 2, 3
- This regimen is FDA-approved for children 12 years and older 2
Alternative Topical Options
- Butenafine twice daily for 2 weeks is an effective over-the-counter alternative if terbinafine is unavailable or not tolerated 1, 2
- Clotrimazole 1% twice daily for 4 weeks provides another alternative, though requiring longer treatment duration 1, 2
- Standard azole treatment duration is 2 weeks, compared to only 1 week with terbinafine 1
When to Use Oral Therapy
- Reserve oral antifungals for extensive infections, treatment failures, or immunocompromised patients 1
- Oral options include fluconazole 50-100 mg daily or 150 mg weekly for 2-3 weeks, itraconazole 100 mg daily for 2 weeks, or terbinafine 250 mg daily for 1-2 weeks 4
Treatment Endpoint and Follow-Up
- Mycological cure, not just clinical improvement, is the definitive treatment endpoint 1
- Continue treatment for at least 1 week after clinical clearing to prevent relapse 1
- If clinical improvement occurs but mycology remains positive, continue current therapy for an additional 2-4 weeks 1, 2
Tinea Capitis (Scalp Ringworm)
Critical Treatment Principle
- Oral antifungal therapy is mandatory for tinea capitis; topical therapy alone is ineffective and should never be used as monotherapy 5
Organism-Directed First-Line Therapy
For Trichophyton species: Terbinafine is the preferred agent due to its fungicidal activity and superior efficacy 5
For Microsporum species: Griseofulvin is the preferred agent 5
- Dosing: 15-20 mg/kg/day (or 10 mg/kg/day per FDA label) for children under 50 kg; 1 g/day for children over 50 kg and adults 5, 6
- Treatment duration: 6-8 weeks 5, 6
- Terbinafine fails against Microsporum because it cannot be incorporated into hair shafts in prepubertal children and doesn't reach the scalp surface where arthroconidia are located 5
When to Start Treatment Empirically
- Start treatment before mycology results if cardinal clinical signs are present: scale, lymphadenopathy, alopecia, or kerion 5
- Collect specimens via scalp scrapings, hair pluck, brush, or swab for microscopy and culture 5
Second-Line Options for Treatment Failure
- Consider factors such as poor compliance, suboptimal drug absorption, organism insensitivity, or reinfection if initial therapy fails 5
- Itraconazole 5 mg/kg/day for 2-4 weeks is effective against both Trichophyton and Microsporum species 5
- Fluconazole is an alternative for refractory cases with favorable tolerability and liquid formulation availability 5
Adjunctive Measures
- Use topical antifungal therapy as adjunctive treatment only 5
- Screen and treat all family members and close contacts, especially for T. tonsurans infections 5
- Cleanse hairbrushes and combs with bleach or 2% sodium hypochlorite solution 5
- Children receiving appropriate systemic and adjunctive topical therapy can attend school or nursery; exclusion is impractical and unnecessary 5
Tinea Pedis (Athlete's Foot)
Treatment Duration
- Topical azoles for 4 weeks or allylamines for 1-2 weeks 7, 4
- Oral therapy may be required for extensive or chronic cases: itraconazole 100 mg daily for 2 weeks or 400 mg daily for 1 week, terbinafine 250 mg daily for 2 weeks, or fluconazole 150 mg weekly 4
Prevention Strategies
For Tinea Cruris
- Cover active tinea pedis with socks before wearing undershorts to reduce direct contamination 1, 2
- Completely dry the groin folds after bathing 1, 2
- Use separate towels for drying the groin and other body parts 1, 2
- Avoid skin-to-skin contact with infected individuals and sharing of personal items 1
General Hygiene Measures
- Practice good personal hygiene and keep skin dry and cool 8
- Avoid sharing towels, clothing, or hair accessories with infected individuals 8
- Clean contaminated clothing and personal items 1
Common Pitfalls to Avoid
- Never use topical therapy alone for tinea capitis - it cannot eradicate scalp infections 5
- Never use terbinafine for Microsporum infections due to poor efficacy 5
- Avoid underdosing griseofulvin, as higher doses are needed due to increasing treatment failures with lower doses 5
- Treatment failure may result from poor compliance, suboptimal absorption, organism insensitivity, or reinfection 2
- Griseofulvin is contraindicated in lupus erythematosus, porphyria, and severe liver disease 1