Coltsfoot, also called Horsehoof and coughwort, is a traditional herbal remedy employed around the world in the treatment of coughs and respiratory problems. Made from the flowers and hoof-shaped leaves of the plant Tussilago farfara, coltsfoot has been employed by traditional herbalists in the form of a tea to treat the persistent cough associated with bronchitis, silicosis and emphysema. Other practitioners have used the herb in blends intended to be smoked to relieve coughs, though the logic behind this use is highly questionable, and could lead to more respiratory irritation.
Widely believed to be a safe compound, researchers in Japan have discovered that the dried flowers and leaves commonly used in Coltsfoot tea contain pyrrolizidine alkaloids which can cause severe liver damage and cancer. While some herbalists think the danger relatively minor when compared to the positive activities of this herb, other practitioners no longer consider coltsfoot an appropriate remedy in light of other effective herbal alternatives.