Some Facts About Comfrey

We often see comfrey is being used as an ingredient for eczema skin care product. What is comfrey actually?

Comfrey did indeed have a wealth of medicinal uses in bygone days. One of its country names was ‘knitbone’, a reminder of its traditional use in healing. The herb contains allantoin, a cell proliferant that speeds up the natural replacement of body cells. Comfrey was used to treat a wide variety of ailments ranging from bronchial problems, broken bones, sprains, arthritis, gastric and varicose ulcers, severe burns, acne and other skin conditions. It was reputed to have bone and teeth building properties in children, and have value in treating ‘many female disorders’. In past times comfrey baths were popular to repair the hymen and thus ‘restore virginity’. Constituents of comfrey also include mucilage, steroidal saponins, tannins, pyrrolizidine alkaloids, inulin, vitamin B12 and proteins.

Internal usage of comfrey should be avoided because it contains hepatotoxic pyrrolizidine alkaloids (PAs) (Note, there are also non-hepatotoxic pyrrolizidine alkaloids.). Use of comfrey can, because of these PAs, lead to veno-occlusive disease (VOD). VOD can in turn lead to liver failure, and comfrey, taken in extreme amounts, has been implicated in at least one death. In 2001, the United States Food and Drug Administration issued a warning against internal usage of herbal products containing comfrey. Symphytine, one of the PAs in comfrey, causes cancer in rats. This was injection of the pure alkaloid. The whole plant has also been shown to induce cancer in rats.

In fact, it would be wisest to refrain from using comfrey for any medicinal purpose whatsoever, given what we now understand about the toxicity and potential long-term consequences of its use. There are plenty of alternative treatments, herbal and non-herbal, that do not entail the same degree of risk.