Echinacea Extract Prevents Cold Symptoms in
Largest Clinical Trial
(AUSTIN,
Texas, October 18, 2012) In the largest clinical trial ever conducted on the
popular medicinal herb echinacea, British researchers have concluded that a
special Swiss echinacea extract is both safe and effective in helping to
prevent symptoms of the common cold. [1]
Researchers
tested 755* healthy people to see if the use of an extract of echinacea root
and herb was safe and effective in preventing cold symptoms over a 4-month
period. The randomized, double-blind, placebo-controlled clinical trial used Echinaforce®,
an alcoholic extract of the leaves (95%) and roots (5%) of organically grown echinacea
(Echinacea purpurea). (Echinaforce is
made by Bioforce AG in Roggwill, Switzerland, and imported into the United
States by Bioforce USA in Ghent, New York.)
The
study took place at the Common Cold Center at Cardiff University in Cardiff,
Wales, of the United Kingdom. Healthy subjects were randomized to either echinacea
or placebo. At the initial clinical visit, subjects received Echinaforce for
one month in addition to completing a diary for documenting potential adverse
side effects, incidences of colds and associated symptoms, and the potential
use of conventional pharmaceutical medication other than the study treatments.
Subjects brought unused treatments and their completed diaries to monthly
clinical visits and were also given kits to take nasal swabs for viral
identification.
The
placebo liquid was comparable in appearance, smell, and taste, with the same
percentage of alcohol and identical packaging as the true echinacea extract. The
total dosage was based on Bioforce AG’s package instructions and consisted of
0.9 ml of extract or placebo 3 times per day in water; the subjects were
instructed to hold this material in their mouths for 10 seconds in order to
achieve maximal local antiviral and anti-inflammatory effects at the pharynx
(throat). If subjects had a cold, they were asked to increase dosage from 2,400
mg of Echinaforce extract daily to 0.9 ml 5 times per day for a total of 4,000
mg of extract.
The
results showed that subjects using the Swiss echinacea extract had significantly
fewer incidences of cold or flu symptoms (149 colds lasting a combined total of
672 days, while subjects in the placebo group reported 188 colds lasting 850 total
days), decreased recurrence of such symptoms (65 vs. 100), respectively), less appearance
of influenza-type viral infections, and had to rely less on the use of
conventional over-the-counter medicines like acetaminophen or ibuprofen — frequently
used by the public to help reduce cold symptoms — than those persons taking the
placebo preparation.
An
important conclusion of this new study is that even after using Echinaforce for
4 months, any adverse effects were mild, and because the adverse effects
experienced with the echinacea extract were observed to be similar to those in
the placebo group, the safety of Echinaforce was evaluated as high. This is
consistent with the safety of other echinacea preparations in additional published
clinical trials as well as the documented general safety of many echinacea
products in general use.
In
a summary and critical review of this clinical trial for the nonprofit American
Botanical Council’s peer-reviewed journal HerbalGram,
author Amy C. Keller, PhD, wrote, “In conclusion…this study claims to be not only
the largest ever conducted on clinical effects of echinacea, but the first to
employ the detection of specific viruses in this manner. The conclusions from
this well-powered, robust clinical trial contribute substantially to the case
for the use of echinacea preparations, particularly this specific formulation,
in common cold prevention.” [2]
Echinaforce
has been shown effective in previous clinical trials, the results of which were
pooled into a 2006 statistical review known as a meta-analysis. [3]
“It
is heartening and refreshing to see such positive conclusions coming from this
largest echinacea clinical trial ever published,” said Mark Blumenthal, founder
and executive director of the American Botanical Council. “While there have been previous clinical
studies producing mixed results on the efficacy of various types of echinacea
preparations, used at different dosage levels, and in different types of study
design, this highly impressive clinical trial is historic due to its size. It
employed a high-quality, well-researched echinacea product, a credible study
design, and had enough people to produce statistically significant positive
results.”
A
detailed summary of the new clinical
trial can be found in a “Research Review” to be published in the November issue
of ABC’s peer-reviewed quarterly journal HerbalGram
and currently available online. [2]
About Echinaforce®
Echinaforce
is produced by Bioforce AG from echinacea plants that are organically grown in
Switzerland and certified by BioSuisse, a federation of Swiss organic farmers
that certifies organic agricultural practices. Echinaforce has been shown to be safe and effective in treating symptoms
of upper respiratory tract infections related to common colds and flus in 3 previous
human clinical trials, as determined by a meta-analysis on such trials in which
the clinical data were pooled, showing a statistically significant trend toward
positive effect. [3] Echinaforce is exported and sold to 28 countries, and is
imported into the United States by Bioforce USA of Ghent, New York, which
markets Echinaforce in the natural food channel.
*
673 subjects completed the trial.
References
1
Jawad M, Schoop R, Suter A, Klein P, Eccles R. Safety and efficacy profile of Echinacea purpurea to prevent common
cold episodes: a randomized, double-blind, placebo-controlled trial. Evid Based Complement Alternat Med.
2012:841315. Epub 2012 Sep 16. (www.hindawi.com/journals/ecam/2012/841315/)
2
Keller AC. Swiss echinacea extract
shown safe and effective in preventing colds in largest echinacea clinical trial. HerbalGram 2012;96:[in press].
3 Schoop R, Klein P, Suter A, Johnston SL. Echinacea in the prevention of
induced rhinovirus colds: a meta-analysis. Clin
Ther. February, 2006;28(2):174-183.