Comfrey - Symphytum officinale

Historical Uses
Pliny writes of comfrey for the treatment of bruises and sprains, and a syrup of the herb or a decoction of its root are used and Dioscorides ‘Materia medica’ also mentions comfrey, saying “The roots below are black on the outside and white and slimy on the inside. …Finely ground and then drunk they are beneficial for those spitting blood and those suffering from internal abscesses. Used as a compress they also seal fresh wounds. They have a joining together effect when cooked with pieces of flesh. They act as cataplasm in the case of inflammation, especially in the anal area.” 1

Culpeper said It is said to be so powerful to knit together; that if they be boyled with dissevered pieces of flesh in a pot, it will join them together again, and a Syrup made thereof is very effectual for all those inward Griefs and Hurts; … and for outward Wounds and Sores in the Fleshy or Sinewy part of the Body whatsoever … A Decoction of the Leaves hereof is available to all the purposes, though not so effectual as the Roots.2


Modern Research
Comfrey has been used for centuries for its wound healing effects, to reduce joint inflammation in rheumatic and arthritic diseases, in broken bones and tendon damage and for its antifungal, anti-inflammatory, antioxidant, and vasoprotective effects. A clinical trial showed that the ointment works significantly better than a placebo ointment, with five times the effect in pain reduction and four times improvement in quality of life. 3

Comfrey is also used as a Tisane for upset stomach, ulcers, heavy menstrual periods, diarrhoea, bloody urine, persistent cough, painful breathing (pleuritis), bronchitis, cancer, and chest pain (angina). It is also used as a gargle for gum disease and sore throat. However, as with Coltsfoot, Comfrey has received bad press in recent years since it is said to contain pyrrolizidine alkaloids particularly echimidine. The Report to the National Institute of Medical Herbalists in September 2018 found little human evidence of harm however in Symphytum officinale which rarely contains echimidine and concluded that when consideration is given to the use of these plants, a risk/benefit analysis should be made before use and the potential benefits weighed against the potential risks. If you are to use Comfrey internally, it should be officinale only and with time-limits and include dietary and supplementary recommendations to support protective liver function during treatment. 4

It is important when using Comfrey to look for Common Comfrey or Symphytum officinale rather than the more poisonous “prickly comfrey” (Symphytum asperum) or “Russian comfrey” (Symphytum x uplandicum) species. The Common Comfrey tends to have cream or pale pink flowers whereas the other two are a darker blue or violet.

 
Topical Uses
Multiple randomized controlled trials have demonstrated the efficacy and safety of comfrey preparations for the topical treatment of pain, inflammation and swelling of muscles and joints in degenerative arthritis, acute myalgia in the back, sprains, contusions and strains after sports injuries and accidents, also in children aged 3 or 4 and over. 5

Dosage
Tisane - 1tsp/5g 3 times per day for no more than 8 weeks a year.
Tincture (leaf). 1:5 50% - dose 2.5-5ml. Maximum weekly dosage – 100ml for no more than 8 weeks.
Tincture (root). 1:5 50% - Maximum weekly dosage – 80ml, for 8 weeks.

Precautions
Avoid during pregnancy.
It is such an excellent and speedy wound-healing remedy that it should not be used on deep wounds or lacerations. It could potentially heal the top layer of skin before the bottom layer, resulting in an abscess.

References
1 Comfrey: ancient and modern uses, the Pharmaceutical Journal 2007
2 Culpeper’s British Herbal
3 (TALHOUK et al., 2007 [1]; NEAGU et al., 2011 [2]; GOKADZE et al., 2013 [3]).
4 Report on the safety of the oral consumption of the PA containing herbs Symphytum officinale, Tussilago farfara and Borago officinalis
5 Staiger C. Comfrey: a clinical overview. Phytother Res. 2012 Oct;26(10):1441-8. doi: 10.1002/ptr.4612. Epub 2012 Feb 23. PMID: 22359388; PMCID: PMC3491633