Image source: http://en.wikipedia.org/wiki/Plik:Symphytum_officinale_01.jpg
Plant family Boraginaceae
Parts used The root and leaves, generally collected from wild plants (Grieve 1971).
Qualities Cold, dry, earthy (Culpeper, 1985).
Constituents
Allantoin, pyrrolizidine alkaloids including intermidine, acetylintermidine, lycopsamine, symphytine, tannins, mucilage, triterpines including triterpine saponins, sterols, salicylic acid, caffeic acid, rosemarinic acid, amino acids (Wichtl, 2004).
Actions
Demulcent, mildly astringent, emollient (Grieve, 1971). Anti-arthritic, anti-inflammatory, promotes callus formation, anti-mitotic (Wichtl, 2004).
Indications
Topically, comfrey is used topically for treatment of ulcers, wounds, joint inflammation, bruises, rheumatoid arthritis, phlebitis, gout, and fractures, in the form of poultices and pastes applied directly to the affected part (Wichtl, 2004).
Comfrey has been incorporated into creams to treat muscle pain (Bone & Mills, 2013). In a randomised, controlled trial investigating the effect of a comfrey-based ointment in the treatment of acute upper and lower back pain, researchers observed a rapid, potent and clinically-relevant reduction in pain (Giannetti, Staiger, Bulitta & Predel, 2009).
Osteoarthritic pain was reduced and mobility of the knee improved with the use of a commercial preparation containing comfrey extract (Kytta-Salbe) (Grube, Grünwald, Krug & Staiger, 2007).
In a 2007 study of ankle sprains, researchers compared comfrey ointment treatment with standard allopathic diclofenac and the comfrey was found to be as effective as the standard treatment (D’Anchise, Bulitta & Giannetti, 2007).
Cautions/Contraindications
Since 1984 the herb has been scheduled as a schedule 5 poison by the National Health and Medical Research Council and is not approved for internal use (Comlaw.gov.au, 2015).
Due to the pyrrolizidine alkaloids compounds present in the herb being known to be hepatotoxic (Bryant, Knights & Salerno, 2006) it may not be suitable for patients with renal problems.
Dosage
Ointment or other preparations containing not more than 35% of root extract, applied 3-4 times per day and only to intact skin (European Scientific Cooperative on Phytotherapy, 2003).
References
Bone, K., & Mills, S. (2013). Principles and practice of phytotherapy (2nd ed., p. 965). Edinburgh: Churchill Livingstone.
Bryant, B., Knights, K., & Salerno, E. (2006). Pharmacology for health professionals. Marrickville, N.S.W.: Elsevier Science.
Comlaw.gov.au,. (2015). Poisons Standard 2012. Retrieved 20 April 2015, from http://www.comlaw.gov.au/Details/F2012L01200
Culpeper, N. (1985). Culpeper's complete herbal. Omega.
D’Anchise, R., Bulitta, M., & Giannetti, B. (2007). Comfrey Extract Ointment in Comparison to Diclofenac Gel in the Treatment of Acute Unilateral Ankle Sprains (Distortions). Arzneimittelforschung, 57(11), 712-716.
European Scientific Cooperative on Phytotherapy,. (2003). ESCOP monographs : the scientific foundation for herbal medicinal products. Thieme.
Giannetti, B., Staiger, C., Bulitta, M., & Predel, H. (2009). Efficacy and safety of comfrey root extract ointment in the treatment of acute upper or lower back pain: results of a double-blind, randomised, placebo controlled, multicentre trial. British Journal Of Sports Medicine, 44(9), 637-641.
Grieve, M. (1971). A modern herbal. New York: Dover Publications.
Grube, B., Grünwald, J., Krug, L., & Staiger, C. (2007). Efficacy of a comfrey root (Symphyti offic. radix) extract ointment in the treatment of patients with painful osteoarthritis of the knee: Results of a double-blind, randomised, bicenter, placebo-controlled trial. Phytomedicine, 14(1), 2-10. doi:10.1016/j.phymed.2006.11.006
Wichtl, M. (2004). Herbal drugs and phytopharmaceuticals. Stuttgart: Medpharm.