Health Tips / Mistletoe

What Is It?

Long before holiday revelers started a custom of kissing under the mistletoe, traditional folk healers used this evergreen shrub to treat various ailments. While they recognized early on that the sticky white berries of the mistletoe plant were poisonous, they brewed the leathery leaves into a therapeutic tea, a remedy that has long endured for ailments ranging from nervous tension to skin sores.

A liquid extract containing key medicinal components of the mistletoe plant has also been used for decades to treat cancer, mainly in Europe and parts of Asia. This practice is considered quite controversial in the United States, however. Recent news reports were sparked by the revelation that actress Suzanne Somers was using mistletoe to treat her breast cancer.

There are several species of mistletoe, including Viscum album (European mistletoe) and Viscum album coloratum (Korean mistletoe), which are used medicinally. All mistletoe species live on trees as semi-parasites, meaning they draw water and minerals from the host tree. Mistletoe bushes grow on the branches of such common tree species as oak, apple, elm, pine, birch, and maple.

The quality and concentration of healing ingredients in commercial mistletoe preparations varies widely–depending on which species is used, which type of tree the plant was attached to, what time of year it was harvested, and other factors.

Health Benefits

Folk healers in Europe and particularly in Asia have long relied on mistletoe for treating everything from rapid heart rates and high blood pressure to epilepsy.

But by far the most popular use of mistletoe today–particularly in Europe–is for treating cancer. Austrian philosopher Rudolf Steiner introduced this idea in 1916 as an outgrowth of a system of thought called “anthroposophy.” According to Steiner, tumors represent an error in the regulation of the physical or spiritual body.

In Steiner’s view, just as mistletoe is a parasite on a host tree, so is cancer a parasite on the human body. Following homeopathic principles of “like cures like” and applying his own version of homeopathic dilution and potentization (the more diluted the substance the more potent it becomes) he felt that tiny doses of the poisonous mistletoe plant could stimulate the body to rectify its so-called “error” in producing malignant tumors. Mistletoe could coax the body back to a state of equilibrium and regulate the area where tumors had been allowed to develop.

Today, it’s estimated that the Germans alone spend more than $30 million annually on mistletoe preparations to fight cancer. A recent survey of 200 physicians in Germany revealed that nearly 80% were inclined to recommend unconventional cancer therapies to their patients, and mistletoe was a clear favorite. Nearly 45% reported prescribing this herb. The anthroposophically based Lukas Clinic in Arlesheim, Switzerland, is devoted almost exclusively to cancer treatment and has been using mistletoe for nearly 75 years.

Specifically, mistletoe may help to:

Fight cancer, prolonging survival. Supporters claim that mistletoe-based cancer preparations will stimulate the release of immune-system cells that hunt down and kill cancer cells in the body. Injection solutions made from naturally fermented mistletoe plant juice (in particular Iscador, a product sold in Europe) have been given to people with cancer of the breast, colon, cervix, rectum, and stomach.
While it’s easy to find laboratory and animal research evidence showing that mistletoe can stimulate the immune system and kill cancer cells, evidence showing that the herb has a similar effect in people is somewhat mixed.

On the one hand, some recent research supports German health authorities, who officially approve of specially prepared mistletoe to treat malignant tumors. An ongoing study published in the May 2001 issue of Alternative Therapies in Health and Medicine found that mistletoe could prolong survival in people with cancer of the breast, rectum, colon, throat, lung, and stomach.

As part of the study, 56 patients were randomly assigned to mistletoe extract and 56 were not. Among those with breast cancer (and lymph node involvement), mean survival time was 4.79 years for women given mistletoe extract, compared with only 2.41 years for those in the control group.

On the other hand, a study published just months earlier–in the February 2001 issue of the European Journal of Cancer–found that a mistletoe extract was no more effective than a placebo in lengthening survival, and that it also failed to alter the immune system in any noticeable way. The five-year study involved nearly 500 patients with a particular type of cancer (head and neck squamous cell cancer), all of whom continued to receive standard cancer treatment along with the mistletoe or placebo.

Dosage Information

Special tips:

–Oral mistletoe preparations include dried leaves for teas, liquid extracts, tinctures, and tablets. All of these can be quite toxic and should only be administered by a physician familiar with their use.

–In Europe and to some extent in Asia, injection and intravenous mistletoe products are commercially available, marketed under such brand names as Iscador, Eurixor, Helixor, Isorel, and Vysorel. While these potent, patented products are not available in the United States, highly diluted (classic homeopathic) versions of a number of them, such as Iscar (made from Iscador) are sold here. However, like all homeopathic injectable medications available domestically, they can only be purchased with a doctor’s prescription.

–The U.S. Food and Drug Administration hasn’t reviewed or approved the use of mistletoe in any form.

For cancer support: In Europe, injections are given in the morning three to seven times a week, with doses adjusted over time based on the patient’s general health, type of cancer, sex, and age. The injection is given near the location of the tumor, and sometimes directly into a tumor on the liver, cervix, and esophagus. Typically, treatment lasts several months to years.

Guidelines for Use

The evidence for mistletoe’s effectiveness in treating cancer is based on injection (or intravenous) formulations–not teas or other oral forms. Note that in the United States, only the diluted (classic homeopathic) injection versions of Iscador and other mistletoe products are available; it’s not clear whether these formulas will work in the same way that the original European mistletoe products do.

General Interaction

Because mistletoe can lower blood pressure, avoid taking it with a blood pressure-lowering drug because your blood pressure could dip dangerously low under such circumstances.

Mistletoe should not be used along with heart medicines; the combination creates an increased risk of cardiac slow-down.

Because mistletoe can cause sedation, don’t take it along with other medications that depress the central nervous system, such as anesthetics, hypnotics and sedatives, narcotics, and tranquilizers.

Possible Side Effects

A generalized fever, chills, and other flulike symptoms may develop with mistletoe injections. This reaction is considered desirable and appropriate by nutritionally oriented physicians because it means the immune system has started take part in the healing process.

Because the mistletoe is homeopathically diluted, relatively few adverse side effects have been reported with its use. Occasionally there is some transient inflammation, redness, and itching around the site of the injection. Allergic reactions are theoretically possible but quite rare.


If you have cancer, see a doctor and discuss your desire to use mistletoe or any other herb. Mistletoe should only be considered as a complement to other cancer treatments, such as chemotherapy and radiation, that your doctor recommends.

Because the mistletoe dosing schedule for cancer treatment is extremely complex, it should only be undertaken by a physician familiar with its use.

It’s particularly important to consult your doctor before taking mistletoe if you have heart condition, gastrointestinal disease, or central nervous system problems.

Never use the fruits (berries) of the mistletoe plant for any medicinal purpose; they are poisonous and can cause vomiting, abnormally low or high blood pressure, seizures, slow heart beat, and even death.

Because mistletoe has been shown to stimulate uterine activity in laboratory animals, pregnant or breast-feeding women should avoid the herb.

Mistletoe cancer treatment with formulations available in Europe (not the homeopathic versions found domestically) can be quite expensive over time, costing as much as $160 (U.S. dollars) a day for nine to 21 days.

Keep the mistletoe plant and all extracts and formulations made with it out of reach of children.

Be well,
David Edelberg, MD