There is confusion in the herb and gardening communities about these two species. See the .gov links at the bottom of this page.
Leaf & Root – these have the same therapeutic uses
Comfrey prefers well watered, rich soil so it is rarely found in the SW outside of well tended gardens. It is fairly easily cultivated in the right conditions. I have only seen it growing wild once in the Southwest, in a damp area near a stream.
Energy and Taste:
Cooling and moistening. The taste is not used as this plant is only for external uses.
Mucilage – best extracted in water
Allantoin, which is responsible for the cell proliferation which aids skin healing. Allantoin is best extracted in hot water.
Its primary use is to assist skin healing and is one of our very best topical herbs. This includes chapped lips, diaper rash, scrapes, road rash, soothes burns, wounds, psoriasis, eczema, topical inflammations, things that tend to be more superficial. Comfrey should not be used on puncture wounds such as stepping on a nail as it can promote surface healing of the skin before the deeper tissue has a chance to heal.
Externally combines very well with many skin herbs, especially calendula and plantain.
Safety Issues & Contraindications:
Comfrey leaves and roots contain pyrrolizidine alkaloids (sometimes referred to as PAs) which can be damaging to the liver with extended use. I recommend folks do not take comfrey internally. The external use of this herb as a poultice, wash or salve is considered very safe. Refer to this link for more details.
Preferred Method of Preparation:
Prepare in a hot water infusion then use this as a soak or external wash on the skin.
Make an herbal oil then prepare as a salve.
Use the fresh leaves as a poultice.
The Plant Profiles are brief materia medica summaries of plants encountered during plant walks or introduced during class on our longer programs. They are presented here to help students organize plant info on an ongoing basis. Although the Profiles are not meant to be comprehensive, they are offered here to the public in the hope that others find these pages useful.