One of the most common uses of comfrey leaf is in an ointment or a poultice applied to sprains, broken bones and other wounds, where it promotes rapid healing of both skin lesions and bone breaks. Comfrey leaf constituents include tannins, rosmarinic acid, allantoin, steroidal saponins, mucilage, inulin, pyrrolizidine alkaloids, Gum, Carotene, Glycosides, Sugars, Beta-sitosterol, Triterpenoids, Vitamin B-12, Protein, Zinc.Comfrey leaf is used in herbal pastes, ointments, tinctures, decoctions, poultices and in cosmetics.It is a popular addition to herbal salves and ointments, which can be used for bruises, sprains, eczema, swellings and burns.