Quote: Comfrey used to be the go-to herbal cure for a lot of issues, but it is a liver toxin when taken internally and should not be ingested, even in tincture form. It's great as a poultice or infusion for muscle aches or sprains, though, and will take down the swelling in varicose veins like nobody's business.
My close friend grows Comfrey and she grows and uses it as an herbal poultice. She's very knowledgeable on the use of tinctures and poultices. One thing she told me about Comfrey is that it speeds the growth of cells, and that is why it helps heal wounds so quickly. But, she also said there's a downside to it - she said if there are cancer cells in the body it can also speed up the growth of them, as well.
I have not been able to confirm that Comfrey does speed up the growth of cancer cells, but the American Cancer Society does not recommend it's use: http://www.cancer.org/treatment/tre...tivemedicine/herbsvitaminsandminerals/comfrey