Tinea Capitis Treatment
Tinea capitis requires oral systemic antifungal therapy—topical treatment alone is insufficient—and the choice of agent should be guided by the causative organism: terbinafine for Trichophyton species and griseofulvin for Microsporum species. 1
Core Treatment Principles
Oral therapy is mandatory because topical agents cannot penetrate deep enough into the hair follicle to eradicate infection. The treatment selection hinges on identifying the causative dermatophyte, as efficacy varies dramatically by species 1.
First-Line Treatment Algorithm
When Trichophyton Species Suspected or Confirmed
(T. tonsurans, T. violaceum, T. soudanense)
Terbinafine is the preferred agent:
- < 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
Terbinafine offers superior efficacy against Trichophyton (response rate 67.9%) and requires shorter treatment duration, improving compliance 1.
When Microsporum Species Suspected or Confirmed
(M. canis, M. audouinii)
Griseofulvin is the preferred agent:
- < 50 kg: 15-20 mg/kg/day (single or divided dose) for 6-8 weeks
- > 50 kg: 1 g daily for 6-8 weeks
Griseofulvin demonstrates significantly higher efficacy against Microsporum (response rate 88.5%) compared to terbinafine. Meta-analysis confirms 8 weeks of griseofulvin is more effective than 4 weeks of terbinafine for confirmed Microsporum infection 1.
Critical caveat: Terbinafine fails against Microsporum because it cannot reach adequate concentrations in prepubertal children's hair shafts and doesn't get excreted in sweat/sebum to reach the scalp surface where Microsporum arthroconidia reside 1.
When to Start Treatment Empirically
Begin treatment before culture results if any cardinal signs are present:
- Scalp scaling
- Cervical/occipital lymphadenopathy
- Alopecia patches
- Kerion formation
However, always obtain fungal culture (via scalp scraping, hair pluck, or brush) before starting therapy to guide subsequent management 1.
Managing Treatment Failure
If clinical improvement occurs but mycology remains positive: Continue current therapy for an additional 2-4 weeks 1.
If no clinical improvement occurs, consider:
- Non-compliance
- Poor drug absorption (griseofulvin absorption improves with fatty food)
- Organism resistance
- Reinfection from household contacts
Second-Line Therapy
Itraconazole is effective against both Trichophyton and Microsporum:
- 50-100 mg daily for 4 weeks, OR
- 5 mg/kg/day for 2-4 weeks
If itraconazole was used first-line, switch to terbinafine for Trichophyton or griseofulvin for Microsporum 1.
Refractory Cases
For exceptional circumstances only: fluconazole or voriconazole 1.
Essential Adjunctive Measures
- Screen household contacts when T. tonsurans is identified—treat positive cases even if asymptomatic with high spore load 1
- Allow school/nursery attendance once appropriate systemic therapy is started 1
- Monitor for mycological cure, not just clinical improvement—repeat cultures until clearance is documented 1
- Consider adjunctive antifungal shampoo (ketoconazole 2% or selenium sulfide 1%) to reduce spore transmission, though this alone is inadequate treatment 2
Important Pitfalls
Licensing considerations: In the UK, griseofulvin remains the only licensed treatment for tinea capitis in children, though terbinafine is widely used off-label based on strong evidence 1. In the US, both griseofulvin and terbinafine granules (for children > 4 years) are FDA-approved 3.
Duration matters: For Trichophyton infections resistant to standard griseofulvin courses, higher doses for 12-18 weeks may be required 1. Don't abandon griseofulvin prematurely for Microsporum—it requires the full 6-8 weeks.
Emerging resistance: While rare in tinea capitis currently, antifungal resistance is rising among dermatophyte infections generally, making species-directed therapy and antifungal stewardship increasingly important 4.