Echinacea (Echinacea purpura ) is a medicinal herb originally used by North American Plains Indians. In the 1870s, an enterprising Nebraska doctor began touting it as a blood purifier capable of curing everything from headache and rheumatism to syphilis and hemorrhoids. Commonly known as the purple coneflower after the large purple blossom that crowns its three-foot stalk, this member of the daisy family is a popular, though still controversial, herbal remedy today in this country and abroad. Two other varieties of echinacea are also commonly used, Echinacea pallida (narrow-leaf purple coneflower) and Echinacea angustifolia (pale purple coneflower).
What is it good for?
Over the past 50 years, hundreds of studies (done primarily in Germany) have examined the immune-boosting effects of purple coneflower juice. In human studies, echinacea taken by mouth shortened the time to get over symptoms of flu-like illness. In some studies echinacea boosted the activity of the immune system. One study found that the immune systems of 134 healthy people became much more active when they took echinacea for five consecutive days. In another trial, 90 people with the flu who took four droppers full of the extract a day improved more rapidly than those who took a dummy version. A 2007 analysis, published in The Lancet Infectious Diseases, showed that echinacea reduced the risk of getting a cold by 58 percent, contradicting previous studies that showed echinacea didn't prevent colds or flu.
However, participants in a study reported in the July 28, 2005, New England Journal of Medicine didn't fare so well. In the study, 437 people were given either echinacea or a dummy version and exposed to the rhinovirus (a type of cold virus). Those who received the echinacea were no less likely to catch a cold and their cold symptoms were no different than participants who received the placebo.
Echinacea ointments are also used to treat superficial wounds, burns, eczema, psoriasis, and other skin conditions.
How does it work?
As yet, nobody knows exactly how echinacea might boost the immune system and keep infections at bay. Unlike a vaccine that protects you from a specific disease, echinacea seems to increase the overall activity of infection-fighting cells. The herb may stimulate white blood cells and lymph cells to attack viruses, bacteria, and abnormal cells. Some research also suggests echinacea gets the body to make more proteins which alert the immune system to defend against bacterial infection.
How safe is it?
Because it might make white blood cells more active, people with auto-immune disorders such as rheumatoid arthritis, multiple sclerosis, and lupus should not use echinacea. People who are HIV-positive or have immune system illnesses should also avoid echinacea. Some experts think that echinacea might lose its effectiveness if used for longer than eight weeks, although it has been used in human studies for up to twelve weeks without problems. On rare occasions echinacea may produce an allergic reaction in some people. If the herb causes any itching or discomfort, stop using it.
How is it taken?
Since other plant extracts have been falsely sold as echinacea, ask an herbal expert, naturopath or pharmacist to suggest a reputable brand. You'll find dried echinacea in herb shops; and echinacea liquid extracts or tinctures, powders, capsules, tablets, creams and gels are available in many stores. Keep in mind that the government does not regulate herbs, so quality and potency can vary widely from product to product.
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