A little known herbal supplement may be as potent as a powerful antihistamine for the care of hay fever.

A Swiss studyindicates that seasonal allergy sufferers who received an extract of butterbur (Petasites hybridus) experienced symptom relief equivalent to patients treated with the antihistamine Zyrtec (cetirizine). The experiment was carried out at four outpatient general medicine and allergy clinics in Switzerland and Germany and the results were published in the January 19, 2002 edition of The British Medical Journal.

The scientists set out to compare the effectiveness and tolerability of the herb, compared to the drug, in patients with seasonal allergic rhinitis (hayfever).In a randomized, double blind, parallel group comparison, the 125 patients participating in the study were treated with either butterbur (61 patients) or cetirizine (64 patients) for two weeks. The patients described similar symptom relief with both treatments. Both medicines were well tolerated.

However, as you might expect, those treated with the antihistamine reported more drowsiness. Despite cetirizine being considered a non-sedating antihistamine, two thirds of the side effects were sedative reactions (drowsiness and fatigue).

According to the researchers, “The effects of butterbur are similar to those of cetirizine in patients with seasonal allergic rhinitis when evaluated blindly by patients and doctors. Butterbur should be considered for treating seasonal allergic rhinitis when the sedative effects of antihistamines need to be avoided.”

Butterbur, also known as butter dock and bog rhubarb, grows in Europe, northern Africa, and southwest Asia. A three foot tall plant, it clusters in wet areas around stream beds.

Nita Bishop is a Clinical Herbalist, naturopathic physician and recent Program Coordinator for Herbal Sciences B.S. degree program at Bastyr University in Washington state. She is a noted expert on Petasites and the European use of this herb. Bishop says that this herb has been used in Europe at least 2000 years. Traditional indications date as far back as the 1st century A.D. when Greek physician Dioscorides stated that "this herb crushed and applied like a plaster is good against harmful decaying conditions which eat away what is still healthy..."

Boasting an enormous leaf with a three foot diameter, probably the largest leaf of all European plants, the name comes from the Greek petasos- a hat worn by shepherds. Folklore has it that field workers used the giant fresh leaves as impromptu hats. The common name butterbur specifically pertains to use of the huge upper leaves to wrap fresh butter during hot weather, according to Bishop.

Butterbur leaves and root are used in folk medicine for spasm, cramp, colic, and headache, including migraine. It is used particularly in cases of acute pain of smooth muscle, such as in the urinary tract, especially when stones are present. This quality also makes it useful for respiratory disorders involving cough and asthma.

A 1998 Polish clinical study examined the influence of petasites on asthma or chronic obstructive bronchitis. All patient groups exhibited a decrease in bronchial reactivity, so petasites might be helpful in improving breathing in patients with asthma or chronic obstructive bronchitis. The asthma connection has stimulated interest in other respiratory applications, such as the recent rhinitis study.

Petasites recently was discovered to be a powerful analgesic. Now being called “European herbal aspirin”, it is getting some surprising new attention. In the last thirty years, studies have shown that petasites inhibits the body’s production of leukotrienes, resulting in antispasmodic and anti-inflammatory activity.Two clinical studies demonstrated its effectiveness as a preventive treatment for migraines.The studies, both double-blind, placebo controlled, involved a total of 128 patients. Butterbur significantly reduced (as much as 60%) the frequency of migraine attacks, compared to placebo. In scientific studies, butterbur produced significantly fewer migraine attacks, fewer migraine days and a reduction in migraine pain.The qualities of this herb lend it to treatment of osteoarthritis.

The main active chemicals are the sesquiterpenes petasin and isopetasin. Petasin is responsible for the antispasmodic and anti-inflammatory properties. Petasites contains potentially toxic pyrrolizidine alkaloid (PA) compounds. Some authorities think that these constituents might be responsible for long term liver damage, although there is no specific evidence that butterbur causes any liver problems. Modern methods extract the offending chemicals, rendering the herb safe.

Human clinical studies are limited, but the potential therapeutic benefits as an anti-inflammatory medicine, as well as pain relieving action offer a promising future for research.

Standardized extracts of butterbur are now available in the United States. Usually, butterbur supplements are PA free and standardized to contain a minimum of 7.5 mg of petasin and isopetasin per tablet. Adults usually take 50-100 mg twice daily with meals. When used to prevent migraines, daily supplementation should continue for four to six months and then taper down to a maintenance dose that gives the best results unless migraine frequency begins to increase.

In the Swiss rhinitis study, the butterbur dose (standardized to 8.0mg of total petasine per tablet) was one tablet, four times daily, for a total of only 32 mg per day. Yet it performed as well as Zyrtec.

There are no known interactions with anti-inflammatory drugs. Do not use Petasites extracts during pregnancy and lactation until we know more about safety. All indications are that the PA free standardized extracts are safe for children.