Mistletoe

What is Mistletoe?

Mistletoe is a hemiparasitic plant that grows on a wide variety of host trees such as pine, oak, birch, and apple. The term hemiparasitic is used to indicate that the mistletoe plant carries out photosynthesis independently but obtains water and minerals from the host.

Scientific Name(s)

Viscum album L. (European mistletoe) and Phoradendron tomentosum (DC.) Engelm. ex A. Gray (Christmas mistletoe).

Common Name(s)

Mistletoe, bird lime, all heal, devil's fuge, golden bough, mistel (German), Iscador

Trade Names

• Iscador

What is it used for?

Traditional/Ethnobotanical uses

Mistletoe preparations have been used medicinally in Europe for centuries to treat epilepsy, infertility, hypertension, and arthritis. The Celtic priests, known as Druids, revered the oak tree and the mistletoe that grew on it, according to Roman author and naturalist Gaius Plinius Secundus (also known as Pliny the Elder). At the winter celebration of Samhain, the sacred oaks were bare except for the green boughs of mistletoe, and this was taken as a sign of eternal fertility. The Celts placed a sprig of mistletoe above the door of their houses and its sacred nature prohibited fighting beneath it. This evolved over centuries into the custom of kissing underneath mistletoe at Christmas. In 1921, the Austrian anthroposophical spiritual leader Rudolf Steiner suggested that mistletoe might be used to treat cancer, based on the observation that mistletoe, like cancer, is parasitic and lethal to its host. Swiss and German clinics were founded to implement this idea and still actively use a mistletoe preparation fermented with a strain of Lactobacillus for 3 days. Mistletoe extracts contain several toxic proteins, several of which are lectins, or proteins capable of binding to specific sugars.

General uses

Mistletoe has been used to treat cancer, although there is a lack of quality clinical trials and no evidence of an effect. Most evidence is ancedotal and based on case reports. Further study is needed. In folk medicine, it has been used for its cardiovascular properties, but its clinical efficacy has not been established. Injectable mistletoe extract is widely used in Europe but is not licensed for use in the United States.

What is the recommended dosage?

Crude mistletoe fruit or herb is used to make a tea to treat hypertension at a dosage of 10 g/day. There are a number of proprietary extracts containing low levels of mistletoe lectin-Ι (ML-Ι) used as adjuvant cancer therapies. These extracts usually are given by intravenous or subcutaneous injection at dosages of 0.1 to 30 mg several times per week. Mistletoe preparations, produced according to anthroposophical methods, are given in incrementally increasing dosages depending on the patient's general condition and response to the injection. Use in pediatric patients has been reported. The pharmacokinetics in healthy adults has been determined.

Contraindications

Data are limited. Use of mistletoe extracts in patients with primary or secondary brain tumors, leukemia, or malignant lymphoma is contraindicated.

Pregnancy/Lactation

Mistletoe contains toxic constituents. Avoid use during pregnancy or lactation.

Interactions

None well documented.

Side Effects

Local reactions following injection include redness, itching, inflammation, and induration at the injection site. Systemic reactions include mild fever or flu-like symptoms. Anaphylaxis has been reported.

Related/similar drugs

Toxicology

Poison centers report toxicity of the whole plant, but especially mistletoe berries. The use of preparations standardized to small doses of ML-Ι or depleted of lectins may reduce toxicity.

References

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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