Elecampane, also called horse-heal, has long been used by the Chinese, Indians, Greeks and Romans to relax and soothe tracheal muscles. The herb owes its healing properties to two specific compounds called inulin and alantolactone. When the linings of the bronchial tubes are swollen and red, it can be very difficult and painful to breathe. Inulin soothes the tubes, while alantolactone cleanses the congestion making breathing easier.