Onychomycosis is a fungal infection of the nail plate that causes nails to become thickened, discolored and brittle. It is caused by fungi called dermatophytes. These fungi invade the nail bed and cause inflammation and damage to the nail plate. The condition usually occurs in people who have weak immune systems.
There are two types of treatments for onychomycosis: topical and oral medications. Topical treatments are applied directly to the affected area. Oral medications are taken orally.Topical treatments for onychomcyosis include antifungal creams, nail polish removers, nail hardeners and nail wraps.
Treatment options for onychomycosis are limited. The most commonly used topical antifungal agents include ciclopirox, amorolfine, terbinafine and efinaconazole. These drugs have been shown to be effective in the treatment of nail infections caused by dermatophytes but their efficacy against other fungal pathogens is less clear.1–3 Ciclop
The most common topical antifungal agents are the allylamines, including terbinafine, naftifine and butenafine. These drugs inhibit fungal ergosterol synthesis by binding to squalene epoxidase in fungi. Terbinafine is a broad spectrum agent that has been shown to be effective against dermatophytes as well as yeasts such as Candida albicans. Topical Antifungals
Treatment Options for Onychomycosis
The most common cause of onychomycosis is dermatophytosis, a fungal infection that affects the nail plate. The fungus can be found in soil or other organic matter such as plants, animals, food products, and household items. It grows best at temperatures between 50°F to 90°F.
– In addition to direct contact with infected material, it may also spread through air currents from one person to another.2 Dermatophyte species vary depending upon where they grow. They tend to infect feet more often than hands because foot skin tends to remain moist longer than hand skin.
– Most cases occur among individuals over age 40 years old. However, children under 10 years old and adults younger than 20 years old are not uncommonly affected.
– Treatment for onychomycois includes both topical and systemic therapies. Systemic therapy involves taking an oral medication. This type of treatment requires multiple doses per day. Topical Therapy For Onychomycoses
Topical therapy is preferred when treating patients with milder forms of disease. There are several different kinds of topical antifungal preparations available. Some contain only 1 drug while others combine 2 or 3 drugs. All these preparations work similarly by inhibiting the growth of fungi.
This preparation contains 0.8% ciclopiro x olamine which inhibits the production of enzymes needed for cell division. Ciclopirox works by interfering with the metabolism of fungi. It does this by blocking the enzyme cytochrome P450 14a-demethylation.4
NEW TOPICAL SOLUTIONS FOR THE TREATMENT OF TOENAIL ONYCHOMYCOSIS
There have been a number of failed development programs over the last 10 to 15 years as researchers attempt to formulate antifungals that show in vitro activity against the common pathogens that cause onychomycosis and to penetrate the nail unit with adequate access to the site of infection. The logical place to start is with the oral antifungal agents already being used to effectively treat dermatophyte onychomycosis. A topical formulation of terbinafine demonstrated mycological and clinical efficacy in vitro and was superior to topical ciclopirox in a Phase 2 study.
Onychomycosis is a common nail disease that is challenging to treat successfully, and therapeutic choices are limited. Oral therapy has been the standard of care for the majority of our patients primarily because of the poor efficacy seen with previously used topical treatment. The availability of an effective, well-tolerated, topical antifungal would be particularly helpful, but options have not been forthcoming because of formulation difficulties hampering effective nail penetration to the site of infection. The development of new topical antifungals for onychomycosis has focused on the following three areas: topical formulations of current oral agents, new formulations of existing topical agents, and new chemical entities. Both the physicochemical properties of the agent and its formulation contribute to efficacy. Two new topical antifungals, efinaconazole 10% solution and tavaborole 5% solution, both appear to offer advantages over ciclopirox 8% nail lacquer, although it is not possible to directly compare the three topical products definitively. Efinaconazole 10% solution applied once daily without nail debridement provides mycologic and complete cure rates 2 to 3 times greater than those reported with ciclopirox 8% nail lacquer applied once daily with nail debridement in a very similar patient population. Based on data available to date, efinaconazole 10% topical solution appears to represent an important advance in the initial treatment and long-term management of this common toenail infection that is often progressive and debilitating.