From the Guidelines
Terbinafine has been developed as a class of ergosterol biosynthetic inhibitor for the treatment of tinea pedis. This antifungal medication works by inhibiting the enzyme squalene epoxidase, which is essential for the biosynthesis of ergosterol, an integral component of the fungal cell wall, as noted in the British Association of Dermatologists' guidelines 1. The action of terbinafine results in both a depletion of ergosterol, which has a fungistatic effect, and an accumulation of squalene, which appears to be directly fungicidal.
Key Points
- Terbinafine is presently the only oral fungicidal antimycotic, with more than 70% of the medication being absorbed when taken orally, and its absorption is not affected by food intake 1.
- The medication has demonstrated high efficacy against dermatophytes, and oral terbinafine, 250 mg, given once daily for 1 week, has similar efficacy to 4 weeks of clotrimazole 1% cream applied twice a day but with faster clinical resolution, as reported in a study on infectious diseases associated with organized sports and outbreak control 1.
- Terbinafine is a recommended treatment option for tinea pedis due to its high potency and favorable clinical outcomes, and it is well tolerated in children, with the most concerning potential adverse events being occasional isolated neutropenia and rare liver failure, typically in people with preexisting liver disease 1.
Treatment Regimen
- Oral terbinafine, 250 mg, can be given once daily for a brief period, such as 1 week, and has similar efficacy to skin-based treatments, but with faster clinical resolution 1.
- Patients should continue the full treatment course even if symptoms improve before completion to prevent recurrence of the infection.
From the FDA Drug Label
Terbinafine, an allylamine antifungal, inhibits biosynthesis of ergosterol, an essential component of fungal cell membrane, via inhibition of squalene epoxidase enzyme. Terbinafine has been developed as a new class of ergosterol biosynthetic inhibitor for the treatment of tinea pedis 2.
- The drug works by inhibiting the squalene epoxidase enzyme, which is necessary for the production of ergosterol.
- This results in fungal cell death due to increased membrane permeability mediated by the accumulation of high concentrations of squalene.