Comfrey has had a reputation as a healing herb since 400 BC, when famed Greek physicians used it to treat a multitude of ailments. The healing compound in comfrey is allantoin. In some way affecting the multiplication of cells and tissue growth, comfrey and allantoin have been used to treat burns, wounds, eczema, psoriasis, bruises, and sprains.

Comfrey is a hardy, leafy perennial, native to Europe and Asia, and naturalized on every other continent. Its inch thick rhizomes are black on the outside and white within. Containing a fleshy, juicy, mucilage, these rhizomes give comfrey another name: slippery root. The medicinal portion of comfrey, allantoin, concentrates in the fastest growing part of the plant. In the winter months, January through March, the fastest growing portion is the rhizome. Come spring, it is in the new young leaves. Harvest of comfrey, and thus allantoin, is done accordingly.