Terbinafine. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic potential in superficial mycoses.

Terbinafine is an orally and topically active allylamine antifungal agent with a primarily fungicidal action in vitro. Its spectrum of in vitro activity includes a broad range of dermatophyte, filamentous, dimorphic and dematiaceous fungi, and some yeast species. In clinical trials, mycological and overall efficacy rates of around 90 and 80%, respectively, have been achieved in cutaneous dermatophyte infections (tinea corporis/cruris and tinea pedis) with terbinafine, administered either orally (250 or 500 mg/day) or topically (a 1% cream applied twice daily). Similar rates of cure have been obtained with oral terbinafine in dermatophyte nail infections after relatively short treatment periods ranging from 3 to 12 months. Topical terbinafine has been effective in approximately 80% of patients with cutaneous candidiasis or pityriasis versicolor. Few comparative data have been published, but generally oral terbinafine appeared to be at least as effective as oral griseofulvin or ketoconazole in tinea corporis/cruris and more effective than griseofulvin in tinea pedis. Both oral and topical terbinafine have been very well tolerated in clinical trials to date, with only minor adverse effects reported. Although further research is required to establish the efficacy of terbinafine in comparison with other available therapies, as well as to fully clarify its tolerability profile, the early results obtained with terbinafine in superficial fungal infections are very encouraging. Terbinafine appears likely to become a first-line therapy for dermatophyte infections, particularly those affecting the nails.