Echinacea no help for colds: study
The herbal remedy echinacea is no better than a placebo at stifling the sneezes, sore throat and fever of common cold sufferers, a study suggests.
In the study of 719 people aged 12 to 80 with early cold symptoms, participants were randomly assigned to receive either no pill, a pill that they knew contained echinacea, or a pill that could be either echinacea or a sugar pill.
Echinacea, also known as purple coneflower, refers to flowers, roots and stems of nine related plants that are native to North America. The herbal product is marketed as helping the immune system fight infections.
Participants who received echinacea had a very slight — seven to 10 hour — decrease in the duration of their cold symptoms that could have been due to chance alone.
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In the study published Tuesday, people recorded their symptoms twice a day for about one week.
There was also no significant decrease in severity of symptoms, Bruce Barrett, the lead researcher and a professor of family medicine at the University of Wisconsin-Madison School of Medicine and Public Health and his co-authors said in the December issue of the Annals of Internal Medicine.
Those who received the herb took the equivalent of 10 grams of dried echinacea root the first day and five grams the next four days.
That dose "did not make a large impact on the course of the common cold, compared either to blinded placebo or to no pills," Barrett said.
"Adults who have found echinacea to be beneficial should not discontinue use based on the results of this trial, as there are no proven effective treatments and no side-effects were seen," Barrett added in a release.
The findings are not convincing in either direction, said Mark Blumenthal, executive director of the American Botanical Council, which follows research on herbal products. He said Barrett is on the group's advisory board.
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, Blumenthal said.
More than 800 products containing echinacea are available. Supplements may contain different parts, or combine echinacea with other herbs that have not been tested.
Use of echinacea is contraindicated during pregnancy and breastfeeding, Health Canada's website says. People with HIV/AIDS, tuberculosis, multiple sclerosis and autoimmune disorders are advised to consult a health-care professional before using echinacea.
Doctors note that antibiotics don't work against cold viruses and can have side-effects. Rest, fluids, pain relievers and over-the-counter medications to relieve symptoms are generally recommended.
The study was funded by the U.S. National Center of Complementary and Alternative Medicine, part of the National Institutes of Health.
The authors include the co-founder of the Australian company that provided the echinacea for the study, but he was not involved in the research.
With files from The Associated Press