Health Canada, Dec 12, 2003
2003-101
December 12, 2003
Advisory
Health Canada advises consumers not to use the herb comfrey or health
products that contain comfrey
OTTAWA - Health Canada is advising Canadian consumers
not to use the herb comfrey or any health products that contain comfrey
because they might contain a compound called echimidine, which may cause
liver damage. As a precaution, consumers are advised not to topically
apply comfrey-containing products to broken skin. This advisory applies to
both approved and unapproved products.
The comfrey herb is found in herbal and homeopathic preparations, and
is marketed to treat digestive problems, lung problems, arthritis, ulcers,
bruises, wounds, and sprains/fractures. Comfrey is also found in lip
balms, burn salves, diaper rash ointments and other therapeutic skin care
products.
There are several different species of comfrey, two of which are
already prohibited from being used in therapeutic products in Canada
because they contain echimidine. These species are prickly comfrey and
Russian comfrey. While not all comfrey products contain echimidine, some
comfrey products do not always identify the species of comfrey in the
product. Therefore, consumers are advised to avoid all products containing
comfrey.
Consumers are advised to check the labels of their herbal and
therapeutic skin care products for the presence of comfrey or echimidine,
and not to use any product whose labels list these ingredients.
What are the risks associated with comfrey use?
There have been several International reports associating the ingestion
of comfrey (teas, capsules, leaves) with liver damage. No cases of liver
toxicity related to comfrey have been reported in Canada.
What is Health Canada doing about this issue?
Health Canada has reviewed recent national and international research,
as well as several reports associating the ingestion of comfrey (teas,
capsules, leaves) with liver toxicity. Other international regulatory
agencies, such as the US Food and Drug Administration, have taken steps to
address liver-related risks.
Health Canada is conducting a market review to determine which health
products on the Canadian market contain comfrey, echimidine or the two
prohibited comfrey species (prickly and Russian). The department is
issuing letters to manufacturers of approved health products that contain
comfrey - those with Drug Identification Numbers (DINs) on the label -
requesting that they submit evidence that demonstrates their products do
not contain echimidine or the two prohibited comfrey species.
Manufacturers, importers and distributors of unapproved products - those
without DINs on the label - are required to remove these products from the
Canadian market immediately. This does not apply to cosmetic products.
Health Canada will keep Canadians informed on any developments related
to this issue, and when the review is complete, will take further action
as appropriate to protect the health and safety of Canadians. As a
precaution, until Health Canada's market review is complete, consumers are
advised to avoid all products containing comfrey.
The same advice applies to comfrey use in animals; however, there are
no authorized products that contain comfrey for veterinary use in Canada.
Comfrey may be identified by the following names:
- Ass Ear
- Black Root
- Blackwort
- Boneset**
- Bruisewort
- Consolida
- Consound
- Gum Plant
- Healing Herb
- Knitback
- Knitbone
- Salsify
- Slippery root
- Wallwort
**"Boneset" is also used as a synonym for 'Eupatorium
perfoliatum,' which is not a comfrey species, and consumers are
advised to call the manufacturer of any product labeled as containing
"Boneset" to confirm the active ingredient.
Consumers should
consult with their health care professional if they have experienced any
of the following symptoms after taking or applying the herb comfrey or
products containing comfrey:
- nausea
- vomiting
- unusual tiredness
- weakness
- loss of appetite
- stomach or abdominal pain
- abdominal swelling
- appearance of blue spider veins on the abdomen
- swelling of the legs/feet
- diarrhea
- jaundice (yellowing of the skin or whites of the eyes)
- brown urine
Consumers are advised to consult with a health care professional
(either conventional or complementary/alternative) about suitable
alternate therapies they may use to replace comfrey.
The text in this article was prepared by Health Canada.