Antifungal agents are also called antimycotic agents.
Polyene antifungals bind to ergosterol, the main sterol in the fungal cell membrane, and cause depolarization of the membrane. This increases the membrane permeability and leads to cell death.
They are not absorbed when given orally, so are used to treat fungal infections of the gastrointestinal tract, such as oral thrush. For treatment of systemic fungal infections they need to be administered intravenously.