What is the treatment for tinea capitis (ringworm of the scalp)?

Treatment of Tinea Capitis

Oral antifungal therapy is mandatory for tinea capitis, with organism-directed treatment being critical: terbinafine for Trichophyton species (2-4 weeks) and griseofulvin for Microsporum species (6-8 weeks). 1

Diagnostic Confirmation Before Treatment

• Collect scalp specimens via scrapings, hair plucking, brush sampling, or swabs for microscopy and culture to identify the causative organism 2, 1
• Use potassium hydroxide (10-30%) preparation for rapid microscopic diagnosis 2, 3
• Culture on Sabouraud agar for at least 2 weeks (3 weeks if T. verrucosum suspected from cattle exposure) 3
• Start treatment immediately without waiting for culture results if kerion, severe scaling, lymphadenopathy, or alopecia are present 3

First-Line Treatment Algorithm

For Trichophyton Species Infections (Most Common in North America)

Terbinafine is the preferred agent due to superior efficacy and shorter treatment duration: 1, 3

• Children <20 kg: 62.5 mg daily for 2-4 weeks 1, 3
• Children 20-40 kg: 125 mg daily for 2-4 weeks 1, 3
• Children >40 kg and adults: 250 mg daily for 2-4 weeks 1, 3
• Gastrointestinal disturbances and rashes occur in less than 8% of children 1

For Microsporum Species Infections (Common in Asia and with Animal Contact)

Griseofulvin is the only effective agent for Microsporum species and remains the only FDA-licensed treatment for tinea capitis in children: 1, 4

• Children <50 kg: 20-25 mg/kg/day for 6-8 weeks 2, 1
• Children >50 kg and adults: 1 g/day for 6-8 weeks 1, 3
• Higher doses (20-25 mg/kg/day) are now recommended due to increasing treatment failures with lower doses 1, 5
• FDA labeling indicates 4-6 weeks for tinea capitis, but clinical guidelines recommend 6-8 weeks 4

Critical pitfall: Terbinafine fails against Microsporum species because it cannot be incorporated into hair shafts in prepubertal children and doesn't reach the scalp surface where arthroconidia are located 1

Second-Line Options for Treatment Failure

If initial therapy fails, consider poor compliance, suboptimal drug absorption, organism insensitivity, or reinfection 1

Itraconazole (effective against both Trichophyton and Microsporum): 1, 3

• 5 mg/kg/day for 2-4 weeks, or
• 50-100 mg/day for 4 weeks 1

Fluconazole (favorable tolerability, available in liquid form): 1, 5

• Particularly useful in younger children who cannot swallow tablets 5
• Effective for refractory cases 1

Adjunctive Measures (Mandatory, Not Optional)

• Use topical antifungal shampoos (selenium sulfide 2%) as adjunctive therapy to reduce spore transmission 1, 5
• Screen all family members and close contacts for asymptomatic carriage, especially for T. tonsurans infections 2, 1
• Cleanse combs, brushes, and fomites with bleach or 2% sodium hypochlorite solution 2, 1
• Avoid sharing personal items like combs, hats, and pillowcases 2

Special Clinical Presentations

Kerion (Inflammatory Mass with Pustules)

• Represents a delayed host inflammatory response to dermatophytes, not bacterial infection 6, 3
• Do not delay systemic antifungal therapy 3
• Consider topical or oral corticosteroids for symptomatic relief of severe inflammation, but this remains controversial 3, 5
• Secondary bacterial infection should not be overlooked; if present, add appropriate antibiotics 6, 2

Dermatophytid ("Id") Reactions

• Pruritic papular eruptions may occur after treatment initiation, particularly around the outer helix of the ear 6, 3
• Represents a cell-mediated host response to dying dermatophytes 6, 3
• Do not discontinue antifungal therapy 6, 3
• Treat symptomatically with topical corticosteroids (or oral if severe) 6, 3

Treatment Endpoint and Monitoring

The definitive endpoint is mycological cure, not clinical improvement 2, 1, 3

• Repeat mycology sampling at the end of standard treatment period 2, 3
• Continue treatment until mycological clearance is documented 2, 1
• Monitor monthly until clearance is achieved 3
• Clinical relapse will occur if medication is not continued until the organism is eradicated 4

School Attendance

• Children receiving appropriate systemic and adjunctive topical therapy can attend school or nursery 1
• Exclusion is impractical and unnecessary 1

Common Pitfalls to Avoid

• Never use topical therapy alone—it cannot eradicate scalp infections 1, 3
• Never use terbinafine for Microsporum infections—it has poor efficacy 1, 7
• Avoid underdosing griseofulvin; higher doses (20-25 mg/kg/day) are needed due to increasing treatment failures 1, 5
• Do not stop treatment based on clinical improvement alone; mycological cure is mandatory 2, 1, 3
• Do not misdiagnose kerion as bacterial abscess and delay antifungal therapy 6, 3