Onychomycosis (Nail Fungus) Referral Guidelines

When to Initiate Referral

  • Failure to respond to therapies above
  • Symptomatic or extensive nail involvement
  • Onychomycosis in immunosuppressed patients

Treatment Basics

  • Nails that are thickened, brittle, discolored, separating from the nail bed, and/or have subungual debris
  • Adjacent skin involvement may be suspicious for fungal infection (red, scaly, or pruritic)
  • Recurrence is common and treatment does not always guarantee a permanent cure

Initial Step

  • Confirm presence of a fungal infection
    • Send an adequate nail clipping for fungal culture
    • The specimen is sent to microbiology in a fungal swab tube (results can take up to 4 weeks)

Mild Onychomycosis (Mild Nail Discoloration of a few Nails)

  • Ciclopirox 8% nail lacquer solution or topical terbinafine 1% cream nightly to the nails until clear

Moderate  to  Severe  Onychomycosis (Brittle Nails, Subungal Debris, etc.) and Fungal Culture is Positive for Dermatophyte

  • Terbinafine (comes in a 250 mg tablet and is given po q day) is preferred if there are no contraindications (e.g. history of significant liver disease or potential drug interaction).
    • If baseline CBC and LFTs are within normal limits, can dose as follows: <20 kg = 5 mg/day, 20-40 kg = 125 mg/day, or >40 kg = 250 mg/day
      Fingernails: 6 week course and toenails: 12 week course
    • Repeat CBC and LFTs after 4-6 weeks on therapy prior to continuing full course