Petasites is a genus of flowering plants in the sunflower family, Asteraceae, that are commonly referred to as butterburs and coltsfoots. They are perennial plants with thick, creeping underground rhizomes and large rhubarb-like leaves during the growing season. Most species are native to Asia or southern Europe.

Tussilago farfara, commonly known as coltsfoot, is a plant in the tribe Senecioneae in the family Asteraceae, native to Europe and parts of western and central Asia. The name "tussilago" is derived from the Latin tussis, meaning cough, and ago, meaning to cast or to act on. It has had uses in traditional medicine, but the discovery of toxic pyrrolizidine alkaloids in the plant has resulted in liver health concerns.