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.
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 medication guide.
What should I discuss with my healthcare provider before taking 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.
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.
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 take 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.
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.
Topical forms of comfrey are intended for external use only.
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 of comfrey?
No information is available regarding a missed dose of comfrey. Consult your doctor,
pharmacist, or health care professional if you require further information.
Where can I get more information about comfrey?
Your pharmacist has information about comfrey written for health professionals that you may read.
What are the possible side effects of comfrey?
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.
Other less serious side effects have not been reported with the use of comfrey, although they
may occur. Talk to your doctor about any side effect that seems unusual or that is especially
bothersome.
What is the most important information I should know about comfrey?
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 should I avoid while taking comfrey?
There are no restrictions on food, beverages, or activity while using comfrey, unless otherwise
directed by your health care provider.
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.
What happens if I have an overdose of comfrey?