MONDAY, Dec. 16, 2002 (HealthDayNews) -- Echinacea, a well-known herb popular as a cold treatment, is no better than a placebo for shortening the duration of the common cold or the severity of its symptoms.
So say researchers from the University of Wisconsin-Madison whose study appears in tomorrow's Annals of Internal Medicine.
But they acknowledge that more research is needed before they can recommend that cold sufferers shelve their echinacea.
The researchers gave the herb in capsule form or a placebo in capsule form to 142 otherwise healthy college students who had just come down with colds. Without knowing if they were getting the herb or the placebo, the students took six grams on the first day and three grams on each subsequent day, for a maximum of 10 days.
No differences between the groups were found in severity of such symptoms as cough, nasal congestion, fever and aches. There was also no significant difference in the duration of the cold between the groups. In each, the cold symptoms lasted two to 10 days. And, in fact, the mean duration in the placebo group was 5.75 days, while in the herb group it was 6.27 days.
Advocates of the herb suspect it increases the activity of the immune system, helping it to fight off a cold.
Despite the study results showing no benefit to the herbal treatment, the lead author, Dr. Bruce Barrett, an assistant professor of family medicine, says he's not ready to give up on echinacea -- a favorite of North American Plains Indians who used it often for medicinal purposes.
"We definitely have to wait and see," says Barrett, whose study was funded by the U.S. Department of Health and Human Services, the National Institutes of Health, and Shaklee Technica, which sells the herb preparations.
The company had no role in the study's design, conduct, reporting of data or the decision to submit the manuscript for publication, the authors note in the paper.
Among the limitations of his study, says Barrett, was the type of herb used. He used a mixture of herb and root, and the mixture has not previously been tested, he says. He says it may be ineffective due to "bioavailability" or other problems.
And healthy undergraduates might not gain as much benefit from the herb as older people, because their immune systems are presumably healthier than those of older adults, Barrett says.
Also, the study was relatively small.
"There's too much evidence [from other studies] that it might work," Barrett says. "I don't think we've proven it doesn't work."
So, to take the herb or not for a cold?
"It's a tricky question because there are not good treatments for the common cold," says Barrett. "If people are going to treat with something, I would prefer echinacea to a decongestant, for instance. Decongestants work like a stimulant and may have harmful effects. And if you believe in echinacea, it would be a good thing to take."
Barrett advises other measures to combat colds, too. "Handwashing to prevent the spread of colds, fluids and rest are all good ideas."
Dr. Ronald B. Turner, a professor of pediatrics at the University of Virginia School of Medicine, praises the study but he's not ready to write off echinacea.
"This study was really quite well done," says Turner, who wrote an editorial to accompany the study report. "I don't think it will be a final word on echinacea." He expects more studies to be released in the future.
The problem, he says, is there are so many variables with the herb. Turner notes there are three different species of the herb that are used for medicinal purposes. "And it is hard to make a recommendation just based on this study," he says.
Turner's advice, for now: "Withhold your judgment on the use of echinacea. I would not use it right now [for colds]." And it's crucial to remember, he adds, that nothing available cures a cold, but rather treats the symptoms.
What To Do
For more information on echinacea, see the
Herb Research Foundation. To learn more about the common cold, check with the National Institute of Allergy and Infectious Diseases.
