Nutritional Food Additives @ - March 13th 2013!

Comfrey Purchase & Information

comfrey powder

Alternative Names

Ass Ear
Blackwort, Black Root, Bruisewort
Consolidae Radix, Consoude, Common Comfrey, Consuelda, Consound, Consoude Officinale
Gum Plant, Grande Consoude
Herbe à la Coupure, Herbe aux Charpentiers, Healing Herb
Knitbone, Knitback
Oreille d'Âne
Slippery Root, Salsify

Make sure must see separate listing for Bugle and Black Root.

Scientific Name

Scientific name of comfrey is Symphytum officinale and it belongs to the Boraginaceae family of plants.

Why do People use Comfrey?

The oral preparations of Symphytum officinale (Comfrey), like comfrey powder, are used for:
• Gastritis
• Ulcers issues
• Excessive menstrual flow
• Diarrhea
• Bloody urine
• Persistent cough
• Pleuritis
• Bronchitis
• For cancer treatment
• Angina complaints
• As a gargle for gum issues
• Pharyngitis

Comfrey is also used topically for:
• Ulcers
• Wounds treatment
• For Joint inflammation
• Bruises
• Rheumatoid arthritis
• Phlebitis
• Gout
• Fractures treatment

Is Comfrey Safe to Use?

Likely Safe
Comfrey is considered safe when utilized for short period and topically on elbow fracture or on unbroken skin parts. For this purpose, 100 mg of hepatotoxic pyrrolizidine alkaloids (PA) should be applied on damaged part on daily basis. Skin easily absorbs it when applied externally.

Likely Unsafe
Comfrey powder is considered unsafe when utilized orally. The reason is that it has a potential to elicit chronic or acute liver toxicity. Comfrey contains hepatotoxic pyrrolizidine alkaloids (PAs). By taking more than 0.1 mg of this compounds daily for long period or taking 1 mg daily for consecutively two weeks can cause liver damage. Some authorities like FDA have suggested the removal of oral products of comfrey.

Likely Unsafe of Pregnant and Lactating Females
Comfrey should be avoided in both lactating and pregnant females, both orally and topically. Further, due to possible carcinogenicity and hepatotoxicity, the PAs in comfrey may be teratogenic.

How effective is Comfrey?

In order to rate the effectiveness of Symphytum officinale, there is lack of authentic information available. According to some preliminary evidences, topical usage of comfrey may decrease tenderness and pain of sprains, bruises and painful conditions of the joints and muscles. However, for other uses of comfrey still more confirmations are required.

What is the Mechanism of Action of Comfrey?

The most effective parts of Symphytum officinale are the rhizome, leaves, and its roots. Comfrey contains lasiocarpine, symphytine and other pyrrolizidine alkaloids (PA), which are carcinogenic, mutagenic, teratogenic and hepatotoxic. PAs are responsible for veno-occlusive liver infection. They harm and destroy centrilobular hepatocytes of the liver. Furthermore, they cause damage to the hepatic veins. PAs could also be harmful for lungs, bringing about pneumonic hypertension. The content of PA of comfrey differs with time of plant and harvesting age. The roots have ten times more PAs than the leaves.

PAs are metabolized in the liver by the enzyme system called cytochrome P450, particularly by CYP 3A4, to poisonous pyrroles and dehydroalkaloids. Enzyme inducers, for example, phenobarbital, appear to increase toxicity level of comfrey powder. Pyrroles are discharged as N-acetyl cysteine conjugates. According to some recent studies, prophylactic N-acetylcysteine administration may decrease toxicity level.

Side effects of Comfrey

A big concern about oral consumption of comfrey is that it has large amounts of hepatotoxic pyrrolizidine alkaloid (PA) in it. These constituents are pneumotoxic, hepatotoxic, mutagenic and carcinogenic. Comfrey can result in diseases like acute veno-occlusive characterized by sudden vomiting, stomach ache, ascites, and also hepatomegaly. In sub-acute disease, comfrey powder can be responsible for a number of side effects that include hepatomegaly, ascites, diarrhea, abdominal pain, abdominal swelling and vomiting issues.

Chronic toxicity appears as progressive ascites and asthenia. Inflammation and hepatic fibrosis may resolve, but the liver functions remain deranged for far too long. This may happen as late as two years after the early ingestion. Different signs and symptoms of pyrrolizidine toxicity may include fatty changes in the liver, bile duct proliferation, cirrhosis, fibrosis and vascular lesions. The use of comfrey powder may lead to as much as 50% mortality. However, the level of toxicity differs from person to person

How Comfrey Interacts with different Supplements & Herbs?

Hepatotoxic Supplements and Herbs
Theoretically, Symphytum officinale may have additive impacts when combined with herbs and supplements that may cause hepatotoxicity. Different herbal products that may be responsible for liver related issues include bishop's weed, chaparral, uva ursi, kava, borage and others.

Herbs with Hepatotoxic Pyrrolizidine Alkaloid (PA)
Theoretically, herbs that induce CYP3A4 may enhance the hepatotoxic PAs alteration level to toxic metabolites. Herbs that induce CYP3A4 include garlic, schisandra,echinacea, St. John's wort and licorice.

How Comfrey Interacts with Drugs?

Cytochrome Inducers
Interaction rating between Cytochrome Inducers and Symphytum officinale is moderate, so be careful about this mixture. Theoretically, those drugs that induce CYP3A4 may enhance comfrey conversion to toxic metabolites, which further increases toxicity. Drugs thatinduce CYP3A4 consist phenobarbital, carbamazepine (Tegretol), rifabutin, rifampin, phenytoin (Dilantin) and some other drugs.

Hepatotoxic Drugs
Interaction rating between comfrey and hepototoxic drugs is moderate, so be careful of this mixture. Comfrey powder, when utilized with hepatotoxic drugs combination, might have additive adverse impacts on liver. Drugs in this category include amiodarone (Cordarone), acetaminophen (Tylenol), isoniazid (INH), carbamazepine (Tegretol), methyldopa (Aldomet), methotrexate (Rheumatrex) and many others drugs as well.

How Comfrey interacts with Food Items?

There is no known interact found between comfrey powder and various food items.

How Comfrey interacts with Lab test?

Liver Function Tests
The hepatotoxic pyrrolizidine alkaloids (PA) in comfrey powder may enhance liver function tests including aspartic acid transaminase (AST, SGOT), alkaline phosphatase, total bilirubin, alanine aminotransferase (SGPT, ALT), lactate dehydrogenase and gamma-glutamyltransferase.

How Comfrey Interacts with Conditions or Diseases?

Damaged, Broken Skin
Symphytum officinale is to be applied only to the unbroken skin. Otherwise, it is contraindicated. If this herb is applied to the broken skin parts, it may toxicity of pyrrolizidine alkaloids (PA).

Liver Disease
Comfrey may worsen liver dysfunction in those patients who are already suffering from liver diseases.

What should be Administration / Dosage of Comfrey?

There is no typical dosage of comfrey herb.


Other products labeled generally comfrey or Symphytum officinale actually consist the more toxic Russian comfrey (uplandicum x Symphytum) or prickly comfrey (Symphytum asperum) species.

General Certificate of Analysis (COA)

Every product that you buy from this site comes with a general certificate of analysis or COA. COA carries all the important information regarding a product like the batch number to which it belongs and its date of manufacture. If you don’t get the COA with your item, please do reach out to our customer support team. For that, kindly use the email box at the end of the homepage of this site. Our dedicated team will try to reach out to you as early as possible. Also please do remember to ask our team about the whole sale price if you intend to buy 25 kilos or more of any product, as the whole sale price varies from product to product. Also please try to avoid the mix up of different items by mentioning the necessary details of a product like its ID, scientific name and trade name. All this info will help us send you the right product.

SKU 657 Comfrey Product Purchase

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"These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure or prevent any disease."

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