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comfrey

Pronunciation: COM free

What is the most important information I should know about comfrey?

Multum donot

Since the use of comfrey has been associated with serious liver damage, ingestion of comfrey is not recommended. The FDA has issued a warning to consumers that the use of comfrey may present a serious health hazard. Also, the topical application of comfrey preparations to broken skin should be avoided.

Comfrey has been associated with cases of severe liver damage. Notify your doctor immediately if you develop nausea, vomiting, abdominal pain, unusual fatigue, loss of appetite, yellow skin or eyes, itching, dark urine, or clay colored stools. These symptoms may be early signs of liver damage.

Comfrey has not been evaluated by the FDA for safety, effectiveness, or purity. All potential risks and/or advantages of comfrey may not be known. Additionally, there are no regulated manufacturing standards in place for these compounds. There have been instances where herbal/health supplements have been sold which were contaminated with toxic metals or other drugs. Herbal/health supplements should be purchased from a reliable source to minimize the risk of contamination.

What is comfrey?

The use of comfrey in cultural and traditional settings may differ from concepts accepted by current Western medicine. When considering the use of herbal supplements, consultation with a primary health care professional is advisable. Additionally, consultation with a practitioner trained in the uses of herbal/health supplements may be beneficial, and coordination of treatment among all health care providers involved may be advantageous.

Comfrey is also known as Symphytum officinale, Russian comfrey, knitbone, knitback, bruisewort, blackwort, black root, slippery root, boneset, consound, gum plant, healing herb, salsify, and wallwort.

Comfrey has been used externally for bruises, sprains, burns, and swelling and as a mouthwash and gargle for gum disease and sore throats. Comfrey has also been used internally for stomach upset, stomach ulcers, hemorrhoids, and diarrhea.

Multum donot

Since the use of comfrey has been associated with serious liver damage, ingestion of comfrey is not recommended. The FDA has issued a warning to consumers that the use of comfrey may present a serious health hazard. Also, the topical application of comfrey preparations to broken skin should be avoided.

Comfrey has not been evaluated by the FDA for safety, effectiveness, or purity. All potential risks and/or advantages of comfrey may not be known. Additionally, there are no regulated manufacturing standards in place for these compounds. There have been instances where herbal/health supplements have been sold which were contaminated with toxic metals or other drugs. Herbal/health supplements should be purchased from a reliable source to minimize the risk of contamination.

Comfrey may also have uses other than those listed in this product guide.

What should I discuss with my health care provider before using comfrey?

Before using comfrey, talk to your doctor, pharmacist, or health care professional if you have allergies (especially to plants), have any medical condition, or if you use other medicines or other herbal/health supplements. Comfrey may not be recommended in some situations.

Multum nopreg

Do not use comfrey without first talking to your doctor if you are pregnant or could become pregnant. It is not known whether comfrey will harm an unborn baby.

Multum nobrfeed

Do not use comfrey without first talking to your doctor if you are breast-feeding a baby. It is also not known whether comfrey will harm a nursing infant.

There is no information available regarding the use of comfrey by children. Do not use any herbal/health supplement to treat a child without first talking to the child's doctor.

How should I use comfrey?

The use of comfrey in cultural and traditional settings may differ from concepts accepted by current Western medicine. When considering the use of herbal supplements, consultation with a primary health care professional is advisable. Additionally, consultation with a practitioner trained in the uses of herbal/health supplements may be beneficial, and coordination of treatment among all health care providers involved may be advantageous.

Multum donot

Since the use of comfrey has been associated with serious liver damage, ingestion of comfrey is not recommended. The FDA has issued a warning to consumers that the use of comfrey may present a serious health hazard. Also, the topical application of comfrey preparations to broken skin should be avoided.

If you choose to use comfrey, use it as directed on the package or as directed by your doctor, pharmacist, or other health care provider.

Standardized topical formulations of herbal/health supplements may provide a more reliable dose of the product.

Multum external

Topical forms of comfrey are intended for external use only.

Multum donot

Do not apply comfrey topically to broken skin.

Store comfrey as directed on the package. In general, comfrey should be protected from light.

What happens if I miss a dose?

Skip the missed dose if it is almost time for your next scheduled dose. Do not use extra comfrey to make up the missed dose.

What happens if I overdose?

Multum emt

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while using comfrey?

Follow your healthcare provider's instructions about any restrictions on food, beverages, or activity.

What are the possible side effects of comfrey?

Multum emt

Although rare, allergic reactions to comfrey may occur. Stop using comfrey and seek emergency medical attention if you experience symptoms of a serious allergic reaction including difficulty breathing; closing of your throat; swelling of your lips, tongue, or face; or hives.

Comfrey has been associated with cases of severe liver damage. Notify your doctor immediately if you develop nausea, vomiting, abdominal pain, unusual fatigue, loss of appetite, yellow skin or eyes, itching, dark urine, or clay colored stools. These symptoms may be early signs of liver damage.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect comfrey?

Interactions between comfrey and other prescription or over-the-counter medicines or herbal/health supplements have not been reported. Talk to your doctor, pharmacist, or health care professional before using comfrey if you are using any other medicines or herbal/health supplements.

Where can I get more information?

Consult with a licensed healthcare professional before using any herbal/health supplement. Whether you are treated by a medical doctor or a practitioner trained in the use of natural medicines/supplements, make sure all your healthcare providers know about all of your medical conditions and treatments.


Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

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