What is the treatment for onychomycosis in an 18-month-old child?

Treatment of Onychomycosis in an 18-Month-Old Child

For an 18-month-old child with onychomycosis, oral terbinafine is the first-line treatment at a dose of 62.5 mg per day if weight is <20 kg for 6 weeks for fingernail infection and 12 weeks for toenail infection. 1

First-Line Systemic Therapy Options

• Terbinafine: First-line treatment for dermatophyte onychomycosis in children and generally preferred over itraconazole 1

  • Dosage: 62.5 mg per day if weight is <20 kg, 125 mg per day for 20-40 kg weight 1
  • Duration: 6 weeks for fingernail infection, 12 weeks for toenail infection 1
  • Monitoring: Baseline liver function tests and complete blood count recommended as it is unlicensed for use in children 1
  • Common adverse effects: Headache, taste disturbance, gastrointestinal upset 1

• Itraconazole: Alternative first-line treatment for dermatophyte onychomycosis 1

  • Dosage: "Pulse therapy" 5 mg/kg per day for 1 week per month 1
  • Duration: Two pulses for fingernails, three pulses for toenails 1
  • Optimally absorbed with food and acidic pH 1
  • Monitoring: Hepatic function tests recommended in patients with pre-existing abnormal results or receiving continuous therapy 1

Second-Line Systemic Therapy Options

• Fluconazole: Consider if terbinafine and itraconazole are contraindicated or not tolerated 1

  • Dosage: 3-6 mg/kg once weekly 1
  • Duration: 12-16 weeks for fingernail infection, 18-26 weeks for toenail infection 1
  • Monitoring: Baseline liver function tests and full blood count 1

• Griseofulvin: Consider as second-line if terbinafine and itraconazole are contraindicated 1, 2

  • Dosage: 10 mg/kg per day (for children older than 1 month) 1
  • Not recommended as first-line due to long treatment duration and low efficacy 1
  • Should be taken with fatty food to increase absorption 1

Topical Therapy Considerations

• Topical therapy may be more effective in children than adults due to their thinner, faster-growing nails 1, 3, 4
• Consider topical therapy for mild cases or as adjunctive therapy 5
• Options include:
  • Amorolfine 5% lacquer: Applied once or twice weekly for 6-12 months 1
  • Ciclopirox 8% lacquer: Applied once daily for up to 48 weeks 1
  • Combination of topical and systemic therapy may provide antimicrobial synergy and improved efficacy 1

Important Clinical Considerations

• Confirm diagnosis through mycological examination before starting treatment 5
• Examine family members for onychomycosis and tinea pedis as familial disease often occurs 1, 4
• Check for concomitant tinea capitis and tinea pedis in the affected child 1, 6
• Children respond better to treatment than adults and show faster response to antifungal therapy 1
• Recurrence rates may be higher in children than adults, requiring vigilance after treatment 4

Prevention of Recurrence

• Apply antifungal powders containing miconazole, clotrimazole, or tolnaftate to shoes and feet 1
• Wear cotton, absorbent socks 1
• Keep nails short 1
• Avoid sharing nail clippers with family members 1
• Consider disinfecting or discarding contaminated footwear 1

Despite the limited number of clinical trials specifically in very young children, systemic antifungal therapy with terbinafine appears to be the most effective approach with a favorable safety profile for treating onychomycosis in an 18-month-old child 1, 7.