Terbinafine. An update of its use in superficial mycoses

Terbinafine is an allylamine antifungal agent which has fungicidal activity against a wide variety of dermatophytes, moulds and certain dimorphic fungi, and fungistatic activity against Candida albicans. Oral terbinafine 250 mg/day is effective in the treatment of superficial dermatophyte infections such as onychomycosis, tinea pedis and tinea corporis/cruris, generally achieving mycological cure in > 80% of patients. The drug is also effective in children with tinea capitis when administered orally in the dosage range 62.5 to 250 mg/day for 4 weeks. Comparative data indicate that oral terbinafine is more effective than continuous or intermittent intraconazole in dermatophyte onychomycosis, and is as effective as itraconazole 400 mg/day in tinea pedis. The drug has shown greater efficacy than griseofulvin in dermatophyte onychomycosis, tinea pedis and tinea corporis/cruris, and comparable efficacy in children with tinea capitis. Additionally, oral terbinafine is more effective than ketoconazole 200 mg/day in tinea corporis/cruris. Topical terbinafine 1% formulations are effective when applied once or twice daily for up to 2 weeks, achieving mycological cure in > 80% of patients with tinea pedis, tinea corporis/cruris, cutaneous candidiasis and pityriasis versicolor. Its formulations are at least as effective as miconazole 2% cream and naftifine 1% gel in tinea pedis, and more effective than clotrimazole 1% cream, bifonazole 1% cream and oxiconazole 1% lotion. Mycological cure rates achieved with terbinafine generally improve after treatment cessation, reflecting the drug's fungicidal mechanism of action and its residual effect in tissue. Terbinafine is well tolerated after oral or topical administration and has a relatively low potential for drug interactions. Pharmacoeconomic data support the use of terbinafine in dermatophyte infections of the skin or nails.

Evidence suggests that oral terbinafine is the treatment of choice for dermatophyte onychomycosis, as it achieves high rates of mycological and clinical cure, is generally well tolerated and has a relatively low potential for drug interactions. It must also be considered a first-line treatment option, along with itraconazole, in cutaneous mycoses which warrant systemic treatment; topical terbinafine is a treatment of choice in less extensive mycoses. The use of terbinafine in non-dermatophyte or mixed infections has not been fully defined.