What are the treatment options for onychomycosis (fungal infection of the fingernails)?

From the Guidelines

For fingernail fungal infections, terbinafine is the recommended first-line treatment due to its higher efficacy and tolerability compared to other options, with a recommended dose of 250 mg per day for 6 weeks. This recommendation is based on the British Association of Dermatologists' guidelines for the management of onychomycosis 2014, which suggests that terbinafine should be considered as the first choice unless there are contraindications 1. The guidelines also mention that terbinafine has been shown to be more effective than griseofulvin in dermatophyte onychomycosis, and that it persists in the nail for a considerable period after elimination from the plasma, allowing for intermittent or 'pulse' treatment regimens.

Some key points to consider when treating fingernail fungal infections include:

• The importance of keeping nails short, dry, and clean to prevent the spread of infection
• Wearing breathable footwear to reduce moisture and prevent the growth of fungi
• Avoiding sharing nail tools to prevent the transmission of infection
• Being patient, as treatment can take several months to be effective, with complete clearing taking 6-12 months

Other treatment options, such as itraconazole and fluconazole, may be considered in certain cases, but terbinafine is generally the preferred choice due to its higher efficacy and tolerability 1. Griseofulvin is also an option, but it has several limitations, including lower efficacy, long treatment duration, and risk of greater drug interactions, making it a less preferred choice unless other drugs are unavailable or contraindicated 1.

In terms of specific treatment regimens, terbinafine is typically prescribed at a dose of 250 mg per day for 6 weeks for fingernail infections, while itraconazole may be prescribed at a dose of 200 mg per day for 12 weeks continuously, or as pulse therapy at a dose of 400 mg per day for 1 week per month, with two pulses recommended for fingernail onychomycosis 1. Fluconazole may be prescribed at a dose of 450 mg per week for 3 months in fingernail infections, and for at least 6 months in toenail infections, although it is generally considered less effective than terbinafine or itraconazole 1.

From the FDA Drug Label

Terbinafine tablets, USP are indicated for the treatment of onychomycosis of the toenail or fingernail due to dermatophytes (tinea unguium). 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

Treatment Options for Fingernail Fungal Infection:

• Terbinafine (PO): indicated for the treatment of onychomycosis of the fingernail due to dermatophytes 2
• Ciclopirox (TOP): indicated as topical treatment for mild to moderate onychomycosis of fingernails without lunula involvement, due to Trichophyton rubrum 3

From the Research

Fingernail Fungal Infection Overview

• Fingernail fungal infection, also known as onychomycosis, is a common condition that affects over 20% of adults over 60 and over 50% of people over 70 4.
• The infection can cause pain, psychosocial problems, and secondary infections, making treatment necessary 4.

Causes and Diagnosis

• Approximately 90% of toenail and 75% of fingernail onychomycosis are caused by dermatophytes, notably Trichophyton mentagrophytes and Trichophyton rubrum 5.
• Diagnosis can be confirmed by direct microscopic examination, histopathologic examination, fungal culture, or polymerase chain reaction assays 5, 6.
• Laboratory confirmation of onychomycosis before beginning a treatment regimen is recommended 5.

Treatment Options

• Oral antifungal therapies, such as terbinafine and itraconazole, are effective but can have significant adverse effects 7, 5.
• Topical monotherapy can be considered for mild to moderate onychomycosis and is a therapeutic option when oral antifungal agents are contraindicated or cannot be tolerated 5, 6.
• Combination therapy and device-based treatments may enhance cure rates, but further study is required 6.
• New and emerging oral and topical therapies are being developed to improve treatment outcomes and patient satisfaction 4, 8.

Safety Considerations

• Oral antifungals can have interactions with cytochrome-p450, leading to adverse events such as hepatic, renal, cutaneous, cardiovascular, neurological, hemopoietic, and obstetric problems 7.
• Laboratory testing of liver function tests is recommended prior to the administration of any oral antifungals, especially when clinically indicated 7.