What is the best treatment for toenail fungus?

Best Treatment for Toenail Fungus

Oral terbinafine is the most effective treatment for toenail fungus (onychomycosis), with higher cure rates compared to other antifungal medications. 1, 2

Treatment Selection Based on Disease Severity

Mild to Moderate Cases (< 80% nail involvement, no lunula involvement)

• Topical antifungal agents can be considered for:
  • Superficial white onychomycosis (SWO) 1
  • Early distal lateral subungual onychomycosis (DLSO) without longitudinal streaks 1
  • Cases where systemic antifungals are contraindicated 1

Topical Options:

• Amorolfine 5% nail lacquer: Applied once or twice weekly for 6-12 months after filing away diseased nail areas; effective in approximately 50% of cases 1
• Ciclopirox 8% nail lacquer: Applied once daily for up to 48 weeks; shows 34% mycological cure rates but only 8% complete clinical cure 1, 3
• Efinaconazole 10% solution: Once-daily application for 48 weeks; mycological cure rates approaching 50% 1

Moderate to Severe Cases (≥ 80% nail involvement or lunula involvement)

• Oral terbinafine (first-line): 250 mg daily for 12 weeks; highest cure rates with strength of recommendation A, level of evidence 1+ 1, 4, 2
• Oral itraconazole (second-line): 200 mg twice daily for 1 week per month for 3 months (pulse therapy) 1, 5
• Oral fluconazole: Used off-label with good efficacy 6
• Oral griseofulvin: No longer a treatment of choice due to lower efficacy (30-40% cure rates), longer treatment duration (12-18 months for toenails), and more drug interactions 1, 2

Comparative Efficacy

• Terbinafine vs. Azoles: Terbinafine shows superior efficacy for both clinical cure (RR 0.82) and mycological cure (RR 0.77) compared to azoles with similar adverse event profiles 2
• Terbinafine vs. Griseofulvin: Terbinafine demonstrates better clinical cure (RR 0.32) and mycological cure (RR 0.64) with fewer adverse events 2
• Azoles vs. Griseofulvin: Similar efficacy but griseofulvin has a higher risk of adverse events (RR 2.41) 2

Special Considerations

For Candida Infections

• Itraconazole is most effective for candidal onychomycosis where the nail plate is invaded 1
• Same dosage as for dermatophytes: 400 mg daily for 1 week per month repeated for 2 months for fingernail infections 1

For Non-dermatophyte Mold Infections

• Itraconazole shows effectiveness (88% cure rate) for onychomycosis caused by certain molds like Aspergillus, Fusarium, and Scopulariopsis brevicaulis 7

Treatment Pitfalls and Caveats

• Diagnostic confirmation: Always obtain mycological confirmation before starting treatment 1, 6
• Clinical vs. mycological cure: Clinical improvement with topical antifungals may not equate to mycological cure, with rates often 30% lower 1
• Treatment failure: Common causes include poor compliance, poor drug absorption, immunosuppression, dermatophyte resistance, and subungual dermatophytoma 1
• Recurrence rate: Approximately 25% of cases recur after successful treatment 8
• Drug interactions: Monitor patients taking terbinafine with tricyclic antidepressants, SSRIs, atypical antipsychotics, beta blockers, or tamoxifen 8

Preventive Measures

• Avoid walking barefoot in public places 8
• Disinfect shoes and socks 8
• Amorolfine can be used as prophylactic treatment for recurrence 1

Adjunctive Measures

• Nail trimming and debridement used concurrently with pharmacologic therapy improve treatment response 8
• A 40% urea ointment is available over-the-counter to help with nail debridement 1