There are nine known species of echinacea, also known as purple coneflower, all native to the United States and Canada. This herb has been used to treat or prevent colds and flu for hundreds of years and is a common ingredient, along with vitamin C, goldenseal, astragalus, and other herbs and nutrients, in immune-boosting remedies.

alt

Echinacea teas and extracts are made of all parts of the plant, from the flower and stems to the roots. The most commonly used species, Echinacea purpurea, is believed to be the most potent, although Echinacea pallida and Echinacea angustifolia are also used frequently. While plenty of research has found echinacea to be ineffective in treating colds, a review of more than 700 studies conducted in 2007 reported that the herb reduced the risk of catching a cold by 58 percent and significantly shortened a cold’s duration. A few small trials have found echinacea to decrease the duration and severity of upper respiratory infections. Echinacea has also been used to treat wounds and skin problems, such as acne or boils, and vaginal yeast infections.

Side effects of echinacea are rare but tend to be more common in people who are allergic to related plants in the aster family, such as chrysanthemums, daisies, marigolds, and ragweed. Ill effects can include rashes and gastrointestinal symptoms or, rarely, anaphylaxis and shock. Also, people with asthma may experience increased symptoms when taking echinacea. Use by children is not recommended because of reports of rash and apparent lack of benefit, according to several studies.

ADDITIONAL FACTS

  1. Echinacea’s genus name comes from the Greek word echino, meaning “spiny” and referring to the flower’s spiny central disk.
  2. According to the National Institutes of Health, about 10 percent of all dietary supplements sold in the United States are echinacea.
  3. Some herbal medicine experts discourage the use of echinacea because long-term use of this herb may cause low white blood cell counts (leukopenia).