Comfrey in topical creams and ointments
Comfrey (Symphytum spp.) is used in a lot of cosmetics because it contains allantoin and is fantastic for preserving skin elasticity. It binds the connective tissue together, helping your skin to remain soft and supple. Comfrey extract also helps to renew & stabilise collagen, and maintain elastin, two critical proteins that support connective tissue and capillary walls.
The worry about comfrey is over products taken internally because of safety concerns with internal use. You can read more about it in this article ‘Is Comfrey Edible?’. These concerns do not apply to topical use except possibly in strong concentrations and there is no restriction on external use. Comfrey leaf skin preparations have not been shown to damage the liver. They are widely used in cosmetics, herbal medicine and also in new pharmaceutical treatments for arthritis. The clinical safety is very high in these new products and comfrey ointments would certainly not be allowed by the FDA or MHRA if there were any safety concerns.
Many people also raise concerns after they have read MSDS sheets on the internet which warn against use on broken or irritated skin. They do not realise that information from MSDS sheets is about the ingredient in its concentrated form and is to provide health and safety advice for use by factory workers in the case of spills, etc.
The information on an MSDS sheet cannot be literally transferred to a finished product as, in a finished product, the ingredient is considerably diluted and also becomes part of a synergistic blend. Although Germany is reported as restricting topical comfrey, please read the following extract from the most recent 2012 research:
“Literature on comfrey often concentrates on PAs, recommending a restriction of the duration of treatment, also with externally applied comfrey preparations. However, in Germany, the restriction limiting application to 4–6 weeks/yr applies only to preparations containing more than 10 mg, but less than 100 mg pyrrolizidine alkaloids (daily allowance; Bundesgesundheitsamt, 1992). Fully licenced medicinal products available today contain depleted or PA-free extracts. The application results in far below the daily allowance of 10 mg. As a consequence there are no restrictions in Germany on these products as regards the duration of treatment (Bundesgesundheitsamt, 1992).”
The above was from a paper called Staiger, C. (2012) Comfrey: A Clinical Overview. Phytotherapy Research Published online in Wiley Online Library (wileyonlinelibrary.com) DOI: 10.1002/ptr.4612 [Merck Selbstmedikation GmbH, Rößlerstr. 96, 64293, Darmstadt, Germany] You will note that the author works for the drug company Merck who are doing clinical trials on a comfrey root ointment. Three pharmaceutical companies (see below) are developing new ointments and would not do so if they were in doubts as to its global marketability.
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, bicentre, placebo-controlled trial. Phytomedicine. 14(1):2-10. [Merck Selbstmedikation GmbH, Rösslerstrasse 96, 64293 Darmstadt, Germany.] Giannetti BM,
Staiger C, Bulitta M, Predel HG. (2010) 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. Br J Sports Med. 44(9):637-41. [CRM Pharmaberatung GmbH, Rheinbach, Germany.]
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):712-6. [Istituto Ortopedico Galeazzi, Milano, Italy.]
As far as the USA FDA is concerned, on their website, comfrey does not appear as a restricted cosmetic ingredient. Further to that in 2008 the FDA looked at PA in comfrey products taken internally. On page 14 of their report they concluded: “The group also determined that the livers of female F344 rats gavaged with one of the three dietary supplements (i) comfrey root extract, (ii) comfrey compound oil, or (iii) coltsfoot root extract, or an extract of a Chinese herbal plant, Flos farfara (Kuan Tong Hua), contained DHP-derived DNA adducts, although at lower levels than that observed with riddelliine. DHP-derived DNA adducts were not detected from the commercial comfrey leaves (in tablet), comfrey leaves (in pepsin), comfrey consoude, or coltsfoot tussilage.” I.e. Comfrey leaf was not found to be problematic.
Other recent research (Rode, 2002) has found that some of the earlier concerns about comfrey may have been overstated.