An In-Depth Look at Comfrey
Latin name of herb: Symphytum officinale, Boraginaceae
Common names: Comfrey, Knitbone, Russian Comfrey
Part(s) used: root, aerial parts (flowers, leaves, stem)
Form(s) used: Infused oil, ointment, tincture
Vitalist actions and energetics: cool, moist, vital stimulant, tonic
Clinical actions: astringent, anti-inflammatory, demulcent, emollient, expectorant, vulnerary, wound healing
Constituents: allantoin, asparagine, inulin, mucilage, phenolic acids (rosmarinic acid), pyrrolizidine alkaloids, starch, tannins, triterpenoids
Primary uses: Externally: Treatment of acne and boils, scars, psoriasis. Assists with healing of bruises, broken bones, fractures, and sprains. Internally: IBS, respiratory conditions (bronchitis pleurisy), stomach ulcers.
Cautions, contradictions, and possible adverse effects: Due to rise of liver toxicity and carcinogenic effects, internal use is not recommended (although there are different reports). Use should be limited to 4-6 weeks. Compounds have been linked to liver toxicity. Otherwise no evidence of liver damage was found in regular consumers (1-10 years use). Due to compounds present in comfrey, supervision of healthcare practitioner is suggested for use during pregnancy or lactation.
Resources: Chevallier p 137; Skenderi p 109; Actions Databse: Comfrey; Tierra P 325-326; AHPA p 838-839