Naftifine hydrochloride is a synthetic allylamine derivative. The following in vitro data are available, but their clinical significance is unknown. Naftifine hydrochloride has been shown to exhibit fungicidal activity in vitro against a broad spectrum of organisms, including Trichophyton rubrum, Trichophyton mentagrophytes, Trichophyton tonsurans, Epidermophyton floccosum, Microsporum canis, Microsporum audouini, and Microsporum gypseum; and fungistatic activity against Candida species, including Candida albicans. Naftifine Hydrochloride Cream USP, 1% has only been shown to be clinically effective against the disease entities listed in the INDICATIONS AND USAGE section.
Although the exact mechanism of action against fungi is not known, naftifine hydrochloride appears to interfere with sterol biosynthesis by inhibiting the enzyme squalene 2, 3-epoxidase. This inhibition of enzyme activity results in decreased amounts of sterols, especially ergosterol, and a corresponding accumulation of squalene in the cells.