What are the treatment options for a fingernail infection?

Treatment Options for Fingernail Infections

Oral terbinafine 250 mg daily for 6 weeks is the first-line treatment for fungal fingernail infections (onychomycosis), with expected cure rates of 80-90%. 1

Diagnosis First

Before initiating treatment, it's crucial to:

• Confirm the diagnosis with appropriate nail specimens:

  • KOH preparation
  • Fungal culture
  • Nail biopsy 1

• Identify the causative organism to guide treatment:

  • Dermatophytes (most common)
  • Candida species
  • Non-dermatophyte molds 1, 2

Treatment Algorithm Based on Infection Type

1. Dermatophyte Onychomycosis (Most Common)

First-line treatment:

• Terbinafine 250 mg daily for 6 weeks 3, 1
• Baseline liver function tests and complete blood count recommended before starting 3
• Common side effects: headache, taste disturbance, gastrointestinal upset 3, 4

Second-line treatment (if terbinafine contraindicated):

• Itraconazole 200 mg daily for 12 weeks continuously, OR
• Itraconazole "pulse therapy" - 400 mg daily for 1 week per month for 2 pulses 3
• Monitor hepatic function in patients with pre-existing issues or on continuous therapy 3

Third-line treatment:

• Fluconazole 150-450 mg weekly for 3 months 3, 1
• Better tolerated but less effective than terbinafine or itraconazole 3

2. Candida Onychomycosis

• Itraconazole preferred over terbinafine 1, 2
• Fluconazole also effective for Candida infections 2, 5

3. Superficial or Limited Infections

For superficial white onychomycosis or early distal lateral subungual onychomycosis with <80% nail involvement:

• Topical options:
  • Amorolfine 5% lacquer applied once or twice weekly for 6-12 months
  • Ciclopirox 8% lacquer applied once daily for up to 48 weeks
  • Tioconazole 28% solution applied twice daily for 6-12 months 3, 1

4. Bacterial Paronychia

• Acute bacterial paronychia:

  • Warm compresses
  • Topical antibiotics with or without corticosteroids
  • Oral antibiotics for more severe cases
  • Surgical incision and drainage if abscess present 6

• Chronic paronychia:

  • Avoid exposure to irritants
  • Combination of broad-spectrum topical antifungal and corticosteroid
  • Topical steroid creams more effective than systemic antifungals 6

Special Populations

Diabetic Patients

• Terbinafine preferred due to lower risk of drug interactions 3, 1
• Itraconazole contraindicated in congestive heart failure 3

Immunosuppressed Patients

• Terbinafine or fluconazole preferred over itraconazole due to fewer interactions with antiretrovirals 3, 1

Pediatric Patients

• Terbinafine dosing based on weight:
  • <20 kg: 62.5 mg daily
  • 20-40 kg: 125 mg daily

  • 40 kg: 250 mg daily

• Duration: 6 weeks for fingernails 3, 1

Management of Treatment Failure

If initial treatment fails, consider:

• Poor compliance
• Poor drug absorption
• Immunosuppression
• Dermatophyte resistance
• Subungual dermatophytoma preventing drug penetration 1

Options include:

• Partial nail removal plus antifungal therapy
• Alternative antifungal drug
• Complete nail avulsion combined with antifungal therapy 1

Prevention of Recurrence

• Keep nails short
• Avoid sharing nail clippers
• Treat concomitant fungal infections
• Treat infected family members 3, 1
• Apply antifungal powders inside shoes if there's also foot involvement 3

Follow-up

• Re-evaluate 3-6 months after starting treatment
• Monitor for at least 48 weeks from treatment initiation
• Additional treatment may be needed if disease persists 1