What are the causes and treatments of onychomycosis (fungal infection of the nail) and onychauxis (nail overgrowth)?

From the Guidelines

Toenail fungus and overgrowth of nails can be effectively treated with oral medications such as terbinafine (250 mg daily for 6-12 weeks) or itraconazole (200 mg twice daily for 1 week per month, for 3-4 months), which have been shown to have high cure rates of 70-80% for toenail infection 1. For mild cases, topical antifungals like clotrimazole or terbinafine applied daily to the affected nails for several months can be used.

• Keep nails trimmed straight across to prevent further irritation and infection.
• Wear breathable footwear to reduce moisture and promote a dry environment.
• Use antifungal powders in shoes to prevent the spread of fungal spores. For overgrown nails (onychogryphosis), regular trimming with proper nail clippers is essential, soaking feet beforehand to soften nails.
• Professional podiatric care may be necessary for severely thickened nails, where they can thin the nails with special tools. It is also important to note that fungal infections thrive in warm, moist environments and can take months to clear due to the slow growth rate of nails, so consistent treatment and patience are necessary for successful outcomes 1. In terms of treatment guidelines, the British Association of Dermatologists recommends that treatment should not be commenced before mycological confirmation of infection, and that terbinafine is superior to itraconazole for the treatment of dermatophyte onychomycosis 1. Additionally, a study published in 2014 found that itraconazole has significantly greater efficacy than terbinafine for the treatment of Candida onychomycosis, and recommends itraconazole as the first-line treatment for this type of infection 1. Overall, the choice of treatment will depend on the severity and type of infection, as well as the patient's individual needs and medical history.

From the FDA Drug Label

Ciclopirox Topical Solution, 8%, (Nail Lacquer), as a component of a comprehensive management program, is indicated as topical treatment in immunocompetent patients with mild to moderate onychomycosis of fingernails and toenails without lunula involvement, due to Trichophyton rubrum The comprehensive management program includes removal of the unattached, infected nails as frequently as monthly, by a health care professional who has special competence in the diagnosis and treatment of nail disorders, including minor nail procedures.

The treatment of toenail fungus and overgrowth of nails with ciclopirox topical solution, 8%, (nail lacquer), involves a comprehensive management program that includes:

• Topical treatment with ciclopirox
• Removal of the unattached, infected nails as frequently as monthly This treatment is indicated for immunocompetent patients with mild to moderate onychomycosis of toenails without lunula involvement, due to Trichophyton rubrum 2.

From the Research

Toenail Fungus and Overgrowth of Nails

• Toenail fungus, also known as onychomycosis, is a difficult-to-treat fungal infection that can cause pain, discomfort, and disfigurement 3.
• Topical treatments, such as amorolfine, ciclopirox, tavaborole, and efinaconazole, are commonly used to treat toenail onychomycosis, but their effectiveness can be limited by the difficulty of penetrating the nail plate 4, 5.
• Combining oral and topical antifungal drugs can be more effective than using a single treatment, with additive or synergistic modes of action enhancing treatment success rates 6.
• The choice of treatment depends on the severity of the infection, the type of fungus causing the infection, and the patient's overall health 7.

Treatment Options

• Topical treatments:
  • Amorolfine 5% nail lacquer 5
  • Ciclopirox 8% nail lacquer 4, 3
  • Tavaborole 5% solution 3
  • Efinaconazole 10% solution 3
• Oral treatments:
  • Terbinafine 6, 7
  • Itraconazole 7
  • Fluconazole 7
• Device-based treatments:
  • 1064-nm Nd:YAG laser 3

Effectiveness of Treatments

• Efinaconazole 10% solution has been shown to be effective in achieving complete cure and mycological cure 3.
• Tavaborole 5% solution has been shown to be effective in achieving complete cure and mycological cure, but may have a higher risk of adverse events 3.
• Ciclopirox 8% lacquer may be effective in achieving complete cure and mycological cure, but may have a higher risk of adverse events 3.
• Amorolfine 5% nail lacquer may be effective in achieving complete cure and mycological cure, but its effectiveness is limited by the difficulty of penetrating the nail plate 4, 5.