Comfrey Medicinal Uses

By | February 12, 2014

Comfrey is a versatile herb that has had much traditional Comfrey medicinal uses. Comfrey, Symphytum officinale, is a native herb found in temperate climates, and a member of the same family as Borage. In Europe, it is known by numerous names including:

  • Boneset
  • Blackwort
  • Slippery root
  • Gum plant

Various varieties of Comfrey are grown in different countries.

Uses and Benefits


The traditionally use of Comfrey roots and leaves are a treatment to help repair broken or weak bones. Its scientific name comes from the Latin word for make firm (confirma) and the Greek word for to unite (Symphytum). The mucilaginous root content is a traditional expectorant and cough medicine, and it can treat gastrointestinal disorders. Other ailments that can be treating with Comfrey include peptic ulcers, and it is often used as an anti-inflammatory healing agent.

Comfrey medicinal uses are not popular in the US now because it is potentially toxic.


The main therapeutic components of Comfrey are found in the roots. These include:

  • Mucilage (fructans)
  • Tannins
  • Allantoin
  • Rosmarinic acid
  • Sarracine
  • Platyphylline
  • Triterpenes
  • Sterols

The most important active constituents are the hepatotoxic pyrolizidine alkaloids, like intermedine and the acetylated derivative nymphetamine and the toxic echimidine.

To date, there have not been any significant clinic trials of Comfrey and its derivativeson humans due to the lack of evidence of Comfrey medicinal uses.

Adverse Effects

There have been several cases of veto-occlusive liver disease reported after Comfrey ingestion. This can result in ascites and hepatic fibrosis. Other known effects of the toxicity of Comfrey include:

  • Curare-like defects
  • Adverse affects in pregnant women
  • Possible carcinogenesis

Individual patient factors will affect the susceptibility, but the herbs are dangerously unpredictable. This has lead to a ban on the systematic use of Comfrey in many countries and the FDA discourage its use. Comfrey from Russia is more toxic than the common Comfrey grown in North America.

Use of Comfrey with other drugs is not known to produce any recognised drug interactions.


Do not take Comfrey internally or orally as it can be toxic. It can be used topically, but only if there is no broken skin. Pregnant and nursing women should avoid all forms of Comfrey.

Preparations and Dosage

It is now more difficult to find preparations of Comfrey root and leaf parts. You can find tablets and other herbal extracts, but the safest way is a very dilute tea or other decoction.

The herb is found in some topical preparations including:

  • Lotions
  • Creams
  • Salves
  • Poultices
  • A liquid gargle

It can be used externally for contusions, bruises and sprains for up to six weeks out of every year, but the toxic side effects mean that it is hard to justify such use even if it is recommended by herbologists.


There is very little in the way of evidence that supports the clinical use of Comfrey and it can have serious hepatotoxic effects. You can use it safely for skin diseases if the skin is unbroken, but do not use it chronically. It might be safe to take oral doses of dilute teas, but Comfrey medicinal uses should really be avoided due to the high toxicity.