Treatment of Tinea Capitis
Tinea capitis requires oral antifungal therapy—topical treatment alone is insufficient—and the choice of agent must be guided by the causative organism: use terbinafine for Trichophyton species and griseofulvin for Microsporum species. 1
Core Treatment Principles
Oral systemic therapy is mandatory because topical agents cannot penetrate the hair follicle to achieve clinical and mycological cure 1. The primary goals are organism eradication, symptom relief, prevention of scarring alopecia, and reduction of transmission.
When to Initiate Treatment
Start treatment immediately if:
- A kerion is present
- Cardinal clinical signs are evident: scaling, lymphadenopathy, or alopecia
These features are strong predictors of tinea capitis, and waiting 2-4 weeks for culture results increases spread risk 1. However, always obtain scalp scrapings, hair plucks, or brush samples for microscopy and culture to guide definitive therapy 1.
First-Line Oral Therapy (Species-Directed)
For Trichophyton Species (T. tonsurans, T. violaceum, T. soudanense):
Terbinafine is the preferred agent 1:
- < 20 kg: 62.5 mg daily for 2-4 weeks
- 20-40 kg: 125 mg daily for 2-4 weeks
- > 40 kg: 250 mg daily for 2-4 weeks
Key advantage: Shorter treatment duration improves compliance 1
Critical caveat: Terbinafine is NOT effective for Microsporum infections—cure rates drop to only 58-59% for M. canis 2, 3. This is because terbinafine cannot reach adequate concentrations in prepubertal children's hair shafts and doesn't reach the scalp surface where Microsporum arthroconidia reside 1.
For Microsporum Species (M. canis, M. audouinii):
Griseofulvin is the treatment of choice 1:
- < 50 kg: 15-20 mg/kg/day (single or divided dose) for 6-8 weeks
- > 50 kg: 1 g daily for 6-8 weeks
Key points:
- Take with fatty food to enhance absorption 1
- Griseofulvin achieves 88.5% cure rates for Microsporum vs. only 67.9% for Trichophyton 1
- Remains the only licensed treatment for tinea capitis in children in the UK 1
- May require doses up to 25 mg/kg/day for 12-18 weeks in resistant Trichophyton cases 1
Second-Line Therapy
Itraconazole is effective against both Trichophyton and Microsporum species 1:
- 50-100 mg daily for 4 weeks, or
- 5 mg/kg/day for 2-4 weeks
Use itraconazole when first-line agents fail or if selected initially, then switch to terbinafine for Trichophyton or griseofulvin for Microsporum if treatment fails 1.
Managing Treatment Failure
First, assess for:
- Non-compliance
- Suboptimal drug absorption
- Reinfection
- Organism insensitivity
If clinical improvement but positive mycology persists: Continue current therapy for an additional 2-4 weeks 1
If no clinical improvement: Switch to second-line therapy immediately 1
Adjunctive Topical Therapy
While topical agents alone are inadequate, they reduce spore transmission 1. Use:
- Ketoconazole 2% shampoo
- Selenium sulfide 1% shampoo
- Povidone-iodine shampoo
Critical Additional Measures
Children on appropriate therapy should attend school/nursery—exclusion is impractical and unnecessary 1
For T. tonsurans cases: Screen all family members and close contacts, as >50% may harbor infection. Treat all positive cases, even asymptomatic carriers with high spore loads 1
Treatment endpoint: Mycological cure, not just clinical improvement. Continue repeat mycology sampling until clearance is achieved 1
Common Pitfalls to Avoid
Using terbinafine empirically without knowing the organism—this leads to treatment failure in Microsporum infections, which comprise 69.8% of cases in some regions 2
Relying on topical therapy alone—this never achieves cure 1
Stopping treatment when symptoms resolve—mycological cure lags behind clinical improvement 1
Not screening household contacts in T. tonsurans cases—this perpetuates reinfection cycles 1
Alternative Agents for Refractory Cases
Fluconazole and voriconazole may be considered in exceptional circumstances when standard regimens fail 1, though licensing restrictions, cost, and limited availability constrain their use.