Comfrey leaf,Information About Comfrey leaf Extract.

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Comfrey Leaf Suggestions and Administrations.

Comfrey Leaf Extract INCI Name Symphytum Officinale Leaf Extract CAS 84696-05-9 EINECS ELINCS No 283-625-3 Comfrey extract photo picture image Combinations: For gastric ulcers and inflammations Symphytum combines well with Althaea and Filipendula. For chest and bronchial troubles it can be used with Tussilago, Marrubium or Inula. The root may be combined with Althaea for topical external application as an ointment. For a poultice, the powdered leaf may be combined with Ulmus and Linum. For the topical treatment of a sprain, it combines well with Jacobaea and Sambucus leaf.

 Caution: Care should be taken with very deep wounds as the external application of Symphytum can lead to tissue forming over the wound before it has healed deeper down, leading to the possibility of an abscess. Excessive internal consumption of the root should be avoided because of the pyrrolizidine alkaloids, which have been linked by some research to liver cancer in rats (on the other hand, there is data to demonstrate that the whole plant actually has a protective effect against liver poisoning, disease and tumours in experimental animals). Hepatic veno-occlusive disease has been related to Symphytum ingestion at high doses over long periods, and the effects of the alkaloids are cumulative. Topical application is safer and more effective for arthritis than internal administration. External application need not be restricted.
 Comfrey Leaf Extract INCI Name Symphytum Officinale Leaf Extract CAS 84696-05-9 EINECS ELINCS No 283-625-3 Comfrey extract photo picture image

 Preparation and Dosage: (thrice daily)

 Leaf: GSL Schedule 1
 Dried leaf: 2-8g or by infusion
 Liquid Extract Leaf: 1:1 in 25% alcohol, 2-8ml
 Root: GSL Schedule 2 - restricted to external use
 Dried root or rhizome: 2-4g in decoction
 Liquid Extract Root: 1:1 in 25% alcohol, 2-4ml
 Ointment Root: 10-15% extractive in ointment base

 Additional Comments: In the past, comfrey baths were popular before marriage to repair the hymen and thus 'restore virginity'. Gerard wrote in 1597 that Comfrey should be '...given to drinke against the paine of the backe, gotten by violent motion as wrestling or overmuch use of women...). A plant high in protein (up to 35%), comfrey is used as an animal feed and organic manure as well as a medicine. The name knitbone derives from its useful property of healing broken bones and wounds; it has even been used by orthopaedic surgeons on complicated bone fractures. This property has been known at least since Roman times, when it was named conferva, meaning to join together. Recently there has been concern that the pyrrolizidine alkaloids contained in comfrey may damage the liver; however, this has been shown only with high doses of plant extracts and not with normal therapeutic doses of the whole herb.

 The fresh leaves and shoots may be cooked as a vegetable or eaten raw in a salad. One of the minerals which has been extracted from comfrey is cobalt, which it uses to produce possibly the only plant source of vitamin B12, making it a valuable dietary supplement for vegans. For the gardener, Symphytum makes an excellent green compost.

 Comfrey is not currently recommended for internal or even limited topical use because of the content of hepatotoxic pyrrolizidine alkaloids (PAs). Older preparations may still be on the market in Europe and Asia. Historically, daily doses of the leaf ranged from 5 to 30 g.

 Comfrey is not recommended for internal or even limited topical use today because of the content of hepatotoxic PAs. Older preparations may still be on the market in Europe and Asia. For informational purposes, typical historical daily doses of the leaf ranged from 5 to 30 g.

 Contraindications: Because of the content of hepatotoxic PAs, comfrey is not recommended for internal use. Patients with hypersensitivity or allergic reactions to the plant should avoid external use. It is contraindicated during pregnancy and lactation and in patients with liver or kidney disease.

 Pregnancy/Lactation:Contraindicated because of documented adverse effects. PAs have abortifacient effects and increase the risk of fatal hepatic veno-occlusive disease.

 Comfrey Adverse Reactions: Internal or extensive topical use of comfrey cannot be recommended because of numerous reports of toxicity, particularly to the liver. An extract of comfrey has been reported to enhance uterine tone. The action of the extract was reported to be stronger than shepherd's purse and St. John's wort, but weaker than that exhibited by German chamomile, calendula, and plantain.

 Toxicology:

 The Food and Drug Administration (FDA) released an advisory in July 2001 recommending that comfrey products be removed from the market because of cases of hepatic veno-occlusive disease. Scientific evidence indicates that any form of comfrey is unsafe and has numerous toxicological effects in animals and humans.

 The FDA released an advisory in July 2001 recommending that comfrey products be removed from the market following several cases of hepatic veno-occlusive disease. Also in 2001, the Federal Trade Commission brought enforcement action against a company marketing comfrey-containing products. The parties agreed to a preliminary injunction that prohibited the company from marketing any comfrey-containing products intended for internal use or use on open wounds, further requiring a warning on comfrey products intended for external use.

 Pancreatic effects:

 The alkaloids of Russian comfrey caused chronic liver damage and pancreatic islet cell tumors after 2 years of use in animal models. Eight alkaloids have been isolated from Symphytum x uplandicum .Alkaloid levels ranged from 0.003% to 0.115%, with highest concentrations in small young leaves.

 Hepatotoxic and carcinogenic risk:

 In the early 1990s, several cases of VOD were reported in humans. VOD involves the destruction or obliteration of small hepatic veins leading to cirrhosis and eventually liver failure. Human poisoning with PAs are usually accidental and may be caused by ingestion of contaminated flour, milk, certain animal products (such as goats, which are resistant to the alkaloids), honey produced by bees that have fed on pyrrolizidine-containing weeds, and consumption of certain herbal or bush teas. It also may be caused by Russian comfrey used in salads.

 Several members of the comfrey family ( Senecio , Heliotropium ) contain related alkaloids reported to cause liver toxicity in animals and humans. Some of these compounds predispose to hepatic tumor development. The conclusion that comfrey is not safe for internal use is based primarily on toxicity studies in rodents administered high doses of purified PAs.

 The carcinogenic potential of S. officinale was tested in rats fed 0.5% to 8% comfrey root or leaves for 600 days. 35 Signs of liver toxicity were seen within 180 days and hepatocellular adenomas were induced in all groups. Urinary bladder tumors also were induced at the lowest comfrey levels. The incidence of liver tumors was higher in groups fed a diet of roots rather than leaves.

 Wheat contaminated with PAs from Heliotropium , ingested by 7,200 Afghans, resulted in a 23% rate of liver damage. An indirect estimate of alkaloid ingestion determined the consumption of toxic alkaloids to be 2 mg per 700 g flour. Based on this value, an extrapolation of 8 to 26 mg of toxic alkaloids per 237 mL comfrey root tea suggests that comfrey ingestion poses a health risk.

 PAs in herbal teas and similar preparations of Symphytum have been shown to cause blockage of hepatic veins, leading to hepatonecrosis. 37 VOD has been reported in a woman who ingested a comfrey-pepsin preparation for 4 months.Four Chinese women who self-medicated with an herbal preparation that contained PAs from an unknown plant source also developed the disease.One man presented with portal hypertension and hepatic VOD and later died of liver failure. It was discovered that he used comfrey in his vegetarian diet.Oral ingestion of pyrrolizidine-containing plants, such as comfrey, poses a great risk because the alkaloids are converted to toxic pyrrole-like derivatives following ingestion.The alkaloids of comfrey applied to the skin of rats were detected in the urine, and lactating rats excreted PAs into breast milk.If animals consume plants containing PAs, they could pass these alkaloids on to humans via milk.

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citations1.Comfrey leaf,Information About Comfrey leaf Extract.

last edit date:29th,June.2009.