Echinacea only offers modest benefit in common cold: study

By Dr. Ananya Mandal, MDDec 21 2010

In a large clinical trial involving more than 700 adults and children researchers showed that the popular herbal remedy Echinacea can cut only half a day from a week long common cold. Echinacea has been marketed for a long time for the common cold. Echinacea, also known as purple coneflower has been shown to have benefits in some earlier studies while some show no benefits.

The trial was funded by the National Center of Complementary and Alternative Medicine, part of the National Institutes of Health. The center, set up to test herbs and other alternative health remedies, has spent $6.8 million testing Echinacea since 2002. Dr. Bruce Barrett and colleagues at the University of Wisconsin for the study used newspaper ads and posters to find volunteers with colds in the Madison, Wis., area. Patients with ages ranging from 12 to 80 took either Echinacea tablets or a dummy pill or no treatment at all. Those among the Echinacea arm were given equivalent of 10 grams of dried Echinacea root the first day and 5 grams the next four days. Twice a day, they graded their symptoms until their cold was gone.

Although there were benefits with Echinacea, it was not statistically significant meaning they could have occurred by chance. Authors write, “…However, the trends were in the direction of benefit [with Echinacea], amounting to an average half-day reduction in the duration of a week-long cold, or an approximate 10 percent reduction in overall severity.” Mark Blumenthal, executive director of the American Botanical Council, which follows research on herbal products said, “It’s not a compelling result in either direction.” Blumenthal added that the study was well designed, used a good quality product at a reasonable dosage and tested Echinacea in a real-world setting, rather than giving colds to research volunteers.

The results were published in the Annals of Internal Medicine. National Center of Complementary and Alternative Medicine director Dr. Josephine Briggs, said there are no plans to support more human research on Echinacea. She said, “I think what we’re seeing is pretty clear. If there’s a benefit of Echinacea, it’s very modest.” Dr. Ronald Turner, of the University of Virginia School of Medicine who has earlier led another study on Echinacea that yielded negative results said, “There’s nothing that’s going to make it go away.”