What is it? Overview Usage Side Effects and Warnings

What is Mistletoe?

European mistletoe, famous during the Christmas season, is a semiparasitic plant that grows on trees in Europe and Asia. Its young leafy twigs and flowers were used as an “all-heal” or panacea, said to be helpful for virtually all diseases. The herb is also said to have played a role in Celtic religious celebrations.

Note: American mistletoe, Phoradendron leucarpum, is related to European mistletoe, but it is thought to be more toxic and has not been well studied.

In the 20th century, mistletoe became popular in Germany through the advocacy of a mystic and philosopher named Rudolf Steiner. The school of medicine he founded, anthroposophical medicine, recommended injectible forms of mistletoe as a treatment for cancer. The initial basis for this use was Steiner’s “clairvoyant” insight. Scientific tests were subsequently conducted with somewhat positive results, but current evidence is far from definitive.

Mistletoe extracts show anticancer effects in the test tube. 1 2 3 4 However, test-tube studies cannot show a treatment effective; only controlled clinical trials can do that. A 2003 review found 10 human trials of injected mistletoe for cancer that met at least minimal scientific standards. 5 Unfortunately, even these studies...

Safety Issues

In large clinical trials, use of injected pharmaceutical-grade mistletoe products has not been associated with serious adverse effects, although pain at the injection site and mild flu-like symptoms are common. Severe allergic reactions may occur rarely. 6 Oral use of a mistletoe product has been associated with hepatitis. 7 Mistletoe berries and perhaps the leaves can cause severe toxicity, especially in children. 8 American mistletoe may be more toxic than European mistletoe. 9 Mistletoe is not recommended for use in young children, pregnant or nursing women, or people with severe liver or kidney disease.