Onychomycosis (OM) refers to a fungal infection that affects the toenails or the fingernails. It may involve any component of the nail unit, including the nail matrix, nail bed, or nail plate. (See the image below.) Although OM is not life-threatening, it can cause pain, discomfort, and disfigurement and may produce serious physical and occupational limitations. Psychosocial and emotional effects resulting from onychomycosis are widespread and may have a significant impact on quality of life.

Signs and symptoms

Patients with OM may present with the following:

  • Initially, complaints about the appearance of the nail, with no physical symptoms.
  • As the disease progresses, interference with standing, walking, and exercising 
  • Paresthesia, pain, discomfort, and loss of dexterity .
  • Loss of self-esteem and inhibited social interaction

OM has five main subtypes, as follows:

  • Distal lateral subungual onychomycosis (DLSO)
  • White superficial onychomycosis (WSO)
  • Proximal subungual onychomycosis (PSO)
  • Endonyx onychomycosis (EO)
  • Candidal onychomycosis

Patients may have a combination of these subtypes. Total dystrophic OM, the most advanced form of any subtype, presents as a thickened, opaque, and yellow-brown nail. Presentation varies by subtype.

Risk factorsFactors that can increase your risk of developing nail fungus include:

  • Older age 
  • Wearing shoes that make your feet sweat heavily
  • Having had athlete's foot in the past
  • Walking barefoot in damp public areas, such as swimming pools, gyms and shower rooms
  • Having a minor skin or nail injury
  • Having a skin condition that affects the nails, such as psoriasis
  • Having diabetes, blood flow problems or a weakened immune system

Management

Medications for onychomycosis can be administered topically or orally. A combination of topical and systemic treatment increases the cure rate. Adjunctive surgical measures may also be used.

Topical therapy for onychomycosis is as follows:

Ciclopirox olamine 8% nail lacquer solution

Amorolfine or bifonazole/urea (available outside the United States)

Efinaconazole 10% topical solution

Tavaborole 0.5% topical solution, an oxaborole solution (boron-containing compound)

Oral therapy for onychomycosis is as follows:

  • Terbinafine
  • Itraconazole
  • Fluconazole and 
  • posaconazole are off-label alternatives

Systemic treatment is always required in PSO and in DLSO involving the lunula region

Nonpharmacologic approaches include the following:

  • Laser treatment
  • Photodynamic therapy
  • Mechanical, chemical, or surgical nail avulsion
  • Chemical removal with a 40-50% urea compound in patients with very thick nails
  • Removal of the nail plate as an adjunct to oral therapy
  • Laser treatment can be combined with topical antifungals.