Terbinafine hydrochloride (HCl) is a medication commonly used to treat fungal infections of the skin and nails. It belongs to a class of drugs called antifungals, specifically allylamines. Here are some key points about terbinafine HCl:

Indications: Terbinafine is primarily used to treat fungal infections such as athlete’s foot (tinea pedis), ringworm (tinea corporis), jock itch (tinea cruris), and fungal infections of the nails (onychomycosis).

Mechanism of Action: Terbinafine works by inhibiting the enzyme squalene epoxidase, which is involved in the synthesis of ergosterol, an essential component of fungal cell membranes. By disrupting the fungal cell membrane, terbinafine effectively kills the fungus and treats the infection.