Onychomycosis: diagnosis and topical therapy

Abstract

Onychomycosis (true fungal infection of the nail plate) is a common malady that may present in several clinical patterns. Because many noninfectious disorders of the nail may masquerade as onychomycosis, the clinical diagnosis must be confirmed by wet mount (potassium hydroxide [KOH] examination), culture, or histology before treatment is begun. Although systemic therapy of onychomycosis with the newer drugs is more effective, the prospect of effective topical therapy is a welcome alternative in many situations. Choices for topical therapy are limited in the United States at this time. As new, improved choices are added to the therapeutic armamentarium, topical therapy my supersede systemic. In addition, the potential for synergism with systemic therapy and for prophylaxis of cleared infections is only now being explored.

REVIEW ARTICLE: Toenail onychomycosis: an important global disease burden

“…The accurate diagnosis of onychomycosis is important for its successful treatment. The cost and long duration of the therapy, the risk of developing adverse drug reactions, and possible interactions with concomitant medications all underline the importance of accurate diagnosis of the condition before commencing therapy (7,74,80,(82)(83)(84)(85). Accurate diagnosis based on the clinical symptoms alone is often difficult.…”

“…Before commencing therapy, it is highly recommended to consider any concomitant medications and the patient's preference, especially when treating persons who have diabetes mellitus, liver disease or are immunocompromised (7,105). Although ketoconazole and fluconazole are often prescribed for the treatment of onychomycosis, only griseofulvin, itraconazole and terbinafine are approved by the US Food and Drug Administration (FDA) and currently licensed for the treatment of this condition in the United States and United Kingdom (1,4,7,44,51,82,99,100,(104)(105)(106).…”

“…The residual lacquer film acts as a drug reservoir and allows the active ingredient to remain in contact with the diseased nail plate for a longer period of time, increasing the potential for better treatment outcome. The residual lacquer film, furthermore, enhances the hydration of the nail plate and amplifies the diffusion of the active drug through the diseased nail plate (2,9,44,82,100,104,122,123).…”

Onychomycosis: beyond cosmetic distress

“…Every patient has the right to receive the best possible therapy, and this should not be empirical. No one should be exposed unnecessary to drug or unwarranted costs 15,20 …”

“…This film acts as a drug depot and, by increasing hydration of the nail, will enhance drug diffusion 30 . Amorolfine 5% nail lacquer (one to two times a week) and ciclopirox 8% nail lacquer (daily) must be applied until clinical cure 20 . Although less effective, tioconazole 28% could be proposed as an alternative to these lacquers 30 …”