Demulcent, mildly astringent and expectorant. As the plant abounds in mucilage, it is frequently given whenever a mucilaginous medicine is required and has been used like Marshmallow for intestinal troubles. It is very similar in its emollient action to Marshmallow, but in many cases is even preferred to it and is an ingredient in a large number of herbal preparations. It forms a gentle remedy in cases of diarrhoea and dysentery. .

For its demulcent action it has long been employed domestically in lung troubles and also for quinsy and whooping-cough. The root is more effectual than the leaves and is the part usually used in cases of coughs. It is highly esteemed for all pulmonary complaints, consumption and bleeding of the lungs. A strong decoction, or tea, is recommended in cases of internal hemorrhage, whether from the lungs, stomach, bowels or from bleeding piles -to be taken every two hours till the hemorrhage ceases, in severe cases, a teaspoonful of Witch Hazel extract being added to the Comfrey root tea.

• External Application

Comfrey leaves are of much value as an external remedy, both in the form of fomentations, for sprains, swellings and bruises, and as a poultice, to severe cuts, to promote suppuration of boils and abscesses, and gangrenous and ill-conditioned ulcers . The whole plant, beaten to a cataplasm and applied hot as a poultice, has always been deemed excellent for soothing pain in any tender, inflamed or suppurating part. It was formerly applied to raw, indolent ulcers as a glutinous astringent. It is useful in any kind of inflammatory swelling.

The reputation of Comfrey as a vulnerary has been considered due partly to the fact of its reducing the swollen parts in the immediate neighborhood of fractures, causing union to take place with greater facility. A salve concocted from the fresh herb will certainly tend to promote the healing of bruised and broken parts. Surgeons have declared that the powdered root, if dissolved in water to a mucilage, is by far beneficial for bleedings and fractures, whilst it hastens the callus of bones under repair. Its virtues as a vulnerary are now attributed to the Allantoin it contains. According to Macalister (British Medical Journal, Jan. 6, 1912), Allantoin  has a powerful action in strengthening epithelial formations, and is a valuable remedy not only in external ulceration, but also in ulcers of the stomach and duodenum. Comfrey Root is used as a source of this cell proliferant Allantoin, employed in the dealing of chronic wounds, burns, ulcers, etc.