Terbinafine hydrochloride (Lamisil® in UK & US) is a synthetic allylamine antifungal. It is highly lipophilic in nature and tends to accumulate in skin, nails, and fatty tissues.
Like other allylamines, terbinafine inhibits ergosterol synthesis by inhibiting squalene epoxidase -- an enzyme that is part of the fungal sterol synthesis pathway that creates the sterols needed for the fungal cell membrane. In layman's terms, it inhibits fungal and bacterial cell wall growth, causing the contents of the cell to be unprotected and eventually die.
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DrugDigest: Terbinafine ( Lamisil ) - Information on dosage, usage, side effects, interactions, and drug comparisons, including generics when available.