What is the most appropriate treatment for onychomycosis of the toenails?

Terbinafine is considered the most appropriate treatment for onychomycosis, particularly in cases involving toenails. It is an allylamine antifungal agent that works by inhibiting the enzyme squalene epoxidase, which is crucial in the synthesis of ergosterol, an essential component of fungal cell membranes. This action not only prevents the growth of fungi but also allows for the clearance of the fungal infection over time as the infected nail grows out.

Clinical studies have demonstrated that terbinafine is generally more effective than alternative antifungal treatments, providing higher cure rates and better patient adherence due to its once-daily dosing schedule and comparatively shorter treatment duration. It is particularly effective against dermatophytes, which are the most common pathogens responsible for onychomycosis.

While itraconazole is another option for treatment, it is often considered when terbinafine is contraindicated or not tolerated. Itraconazole may also have interactions with certain medications and can require dose adjustment based on the patient's condition and liver function. Micafungin is primarily used for systemic fungal infections and is not typically used to treat nail fungus. Griseofulvin is generally used for superficial fungal infections and has lesser efficacy against nail infections compared to terb