What medication is used to treat hair loss due to fungal scalp infection?

Treatment of Hair Loss Due to Fungal Scalp Infection (Tinea Capitis)

Oral antifungal therapy is essential for treating hair loss from fungal scalp infections, with griseofulvin or terbinafine as first-line agents, chosen based on the causative organism. Topical therapy alone is ineffective and should never be used as monotherapy. 1

First-Line Oral Antifungal Selection

The choice between griseofulvin and terbinafine depends critically on the causative dermatophyte species:

For Microsporum Species (M. canis, M. audouinii)

• Griseofulvin is superior and should be the first choice 1
• Dosing: 15-20 mg/kg/day (or 20-25 mg/kg/day) for 6-8 weeks 1, 2
• For patients <50 kg: 15-20 mg/kg/day in single or divided doses 1
• For patients >50 kg: 1 g/day in single or divided doses 1
• Take with fatty food to enhance absorption 1, 3
• Griseofulvin remains the only licensed treatment for tinea capitis in children in the UK 1

For Trichophyton Species (T. tonsurans, T. violaceum, T. soudanense)

• Terbinafine is more effective and should be the first choice 1, 2
• Weight-based dosing for 2-4 weeks: 1, 2
  • <20 kg: 62.5 mg/day
  • 20-40 kg: 125 mg/day

  • 40 kg: 250 mg/day

• Shorter treatment duration improves compliance compared to griseofulvin 1

When to Initiate Treatment

Start treatment immediately if clinical features strongly suggest tinea capitis, even before culture confirmation, particularly when: 1

• A kerion (boggy, inflammatory mass) is present 1
• Cardinal signs are evident: scaling, lymphadenopathy, or alopecia 1
• Waiting 2-4 weeks for culture results risks permanent scarring and increased transmission 1

However, always obtain specimens (scalp scrapings, hair plucks, or brush samples) for microscopy and culture before starting treatment to guide therapy and confirm diagnosis. 1, 4

Essential Adjunctive Measures

Antifungal Shampoos (to Reduce Spore Transmission)

• Ketoconazole 2% shampoo is recommended as adjunctive therapy 2
• Alternative options: selenium sulfide 1% or povidone-iodine shampoo 1
• These reduce transmission but cannot cure the infection alone 1

Topical Corticosteroids

• May provide symptomatic relief for inflammation and itching 2
• Particularly useful for inflammatory variants like kerion 2

Treatment Failure Management

If no improvement after standard treatment duration, consider: 1

• Non-compliance with medication regimen
• Suboptimal drug absorption (ensure griseofulvin taken with fatty food)
• Wrong organism identification (Microsporum treated with terbinafine, or vice versa)
• Reinfection from household contacts or fomites

For Treatment Failures:

• Microsporum infections: Extend griseofulvin to 12-18 weeks if needed 1
• Trichophyton infections: May require higher doses or longer duration 1
• Consider switching agents if organism was misidentified 1

Alternative Second-Line Agents

When first-line agents fail or are contraindicated:

• Itraconazole: Comparable efficacy to griseofulvin for M. canis (88% cure rate) 5
• Fluconazole: 100-200 mg daily for 7-14 days for moderate to severe infections 2
• These require 2-4 weeks of treatment 2

Critical Contraindications and Cautions

Griseofulvin Contraindications:

• Lupus erythematosus 1, 2
• Porphyria 1, 2
• Severe liver disease 1, 2
• Drug interactions: rifampicin decreases levels, cimetidine increases levels 1

Common Pitfalls to Avoid:

• Never use topical antifungals alone - they cannot penetrate hair follicles adequately 1
• Do not confuse with alopecia areata - fungal infections have scaling and inflammation 1
• Do not mistake kerion for bacterial abscess - this leads to inappropriate antibiotic-only treatment 1
• Do not stop treatment prematurely - complete the full course even if clinical improvement occurs early 4

Monitoring and Follow-Up

• Repeat mycology sampling at end of treatment to document mycological cure, not just clinical improvement 4
• Continue treatment until mycological clearance is confirmed 4
• Screen household contacts for asymptomatic carriage, especially with T. tonsurans 4
• Disinfect combs, brushes, and avoid sharing personal items 4

Key Clinical Algorithm Summary

1. Obtain specimens for culture before treatment 1, 4
2. Start treatment immediately if kerion or strong clinical suspicion 1
3. Choose agent based on local epidemiology or suspected organism: 1
   • Microsporum → Griseofulvin 6-8 weeks
   • Trichophyton → Terbinafine 2-4 weeks
4. Add antifungal shampoo (ketoconazole 2%) to reduce transmission 2
5. Adjust therapy once culture identifies organism 1
6. Confirm mycological cure with repeat sampling 4