Mistletoe (Viscum album L.) belongs to the family of the loranthaceae. It is one of the very few parasitic plants of Europe and it lives on deciduous trees and conifers, depriving them of water and nutrients. Usually, mistletoes grow to be round bunches that can reach a diameter of up to one meter.

Since ancient times, the mistletoe has been known as a medicinal plant and also played an important role in the cultic rituals of Celtic priests. Its medicinal uses were likewise maintained through the Middle Ages, mainly for the continuous treatment of mild forms of high blood pressure and the prophylaxis against arteriosclerosis.

The main agent of the mistletoe is viscotoxin.