Symphytum officinale L., (Comfrey) roots have been used for medicinal purposes since the 16-century. In the Middle Ages people used to cultivate Comfrey in their gardens; it was a famous remedy for broken bones.

The roots are used as an expectorant and diuretic to treat inflammation of the urinary tract, damaged mucous membranes of the stomach and pharynx and also to treat gastric and duodenal ulcers. It is mainly used externally promoting tissue growth the healing of cuts, eczema, frostbite, burns etc. Comfrey is used as a mouth wash to treat oral disorders.(1)

A mucilaginous decoction from the plant has a healing action when applied to a wound. This is thought to be due to the presence of allantoin. Two alkaloids; saccacin and platyphtlin have been found to reduce excess activity of the digestive system and act against stomach ulcers.

References:
		1. Opletal L, Volak J. Healing Plants (2000) p.154-155

Further information:
		"Comfrey" at HerbMed.org