Echinacea is a spiny looking plant with purple leaves radiating from the center and is a derivative of the purple coneflower. It grows to be one to two feet in height and is a member of the daisy family. Three types of the plant are used for medical purposes. They are Echinacea purpurea, Echinacea angustifolia, and Echinacea pallida. Mainly the roots, the seeds, and the leaves are extracted for medicinal usage. Many people believe the herb to be a remedy for ailments such as the common cold or the flu, which explains why the citizens of the United States spend $3 million annually on the drug. As a consequence of its popularity however, certain places in both the United States and Europe have restricted the harvesting of Echinacea and have put it on the endangered species list. The herb has not yet been approved by the Food and Drug Administration as either safe or effective in the forms that manufactures are distributing. (http://www.rxlist.com/cgi/alt/echinacea.htm)
The Native Americans were the first people to use Echinacea for medical purposes. They believed that sufferers with minor disorders such as colds to more serious conditions like snakebites could benefit from usage. They even utilized the herb for veterinary medicine for horses. In the early 1900’s, the herb gained commercial popularity and was widely sold throughout the United States. Consumers had high hopes that Echinacea would cure or prevent many different illnesses. In 1910 however, the American Medical Association claimed that the drug was useless but many people continued to purchase and use the supplement until about 1930. The American people grew disinterested in Echinacea while some Europeans, particularly German citizens, kept using and studying it. Because they continued their studies, they have the best research today on the topic. Echinacea was sold again in the United States in the 1980’s and is still one of the best selling herbs today (http://www.ibiblio.org/herbs/immune.html)
Hype: What’s on the Internet
Many different claims are made about the workings of Echinacea. According to The Herbal Marketplace, which sells Echinacea on the World Wide Web, the supplement is a “natural anti-biotic” that enhances blood flow and circulation and remedies enlarged prostates. The advertisement tells readers that the herb also cleanses lymphatic and glandular tissue. In combination with other herbs, the company boasts that the drug will “promote optimal immune system function”.
Whole Health Discount Center’s web page has an in depth overview of the herbal supplement. In the summary, it is clearly stated that “The ability of Echinacea to stimulate the immune system is extremely well documented”, yet other than a brief list of five references at the bottom of the article, there is no mention of exactly what documentation has been made. The explanation of how the herb works is based on the activity of two polysaccharides, which are large sugar molecules. The article is even more vague when it sidesteps describing exactly how these molecules aid in the immune enhancing process “…these polysaccharides activate the immune system in so many ways that a thorough discussion of them would quickly lose the reader…” Ending the discussion of how Echinacea works is a ploy to hook the consumer to buy the product “…This is an herb that deserves a space in your medicine cabinet”.
serves as another website that provides
several different ailments that Echinacea purportedly cures or helps to
alleviate. The “Health Library”
section of the ad states that the herb can be used for skin disorders such as
boils, abscesses, and carbuncles. The
description of the supplement in the advertisement continues and says that
Echinacea can also be used as an antiseptic for burns and skin ulcers.
Directly next to the description of the herb and the list of maladies
that it is used for is a price list.
World Online explains exactly how Echinacea works as an immunostimulant,
which basically means that it boosts the immune system.
It does this by inhibiting an enzyme called hyaluronidase.
When foreign agents enter the body, this enzyme causes the barrier
against pathogens to break, which allows infections to spread.
By stopping the hyaluronidase from weakening the body’s defense,
Echinacea is helping the cells of the immune system to stay healthy and
unharmed. The herb also stimulates the production of macrophages, large
cells working for the immune system, and phagocytosis, the eating of the
foreign agents. A complex sugar
in the supplement called Echinacen B is also involved in the fight to stay
healthy by regenerating damaged tissues and ridding of the pathogens.
According to Barbara Fahs’ article"Echinacea:
More Than Just a Pretty Flower", Echinacin also “increas[es] the
chemical recognition of an invading pathogen”.
Therefore the body’s defense system responds faster to an invader and
more cells are sent to the site at and earlier time.
Most sites selling Echinacea do not list
warnings or side effects. If they
do, it is a concise list that is fairly vague. For example, the only warning that Vitacost.com
provides is to “Keep out of reach of children”. Netgrocer.com
only warns to “not use this product if pregnant or nursing”.
Herbs Online states that there are no known side effects but sometimes
Echinacea may cause dizziness or nausea.
Therefore they also recommend that people with vertigo or anemia should
not use the product. Because the
Food and Drug Administration have not approved Echinacea, the companies
selling it do not have any rules or regulation regarding the marketing of the
product. Consequently, no warnings have to be given to the consuming
public about the possible side effects that could occur while taking the drug.
Research Foundation, which is the only site noted that is not promoting
the product, gives a fairly detailed account of the safety of Echinacea.
On its web site, the foundation maintains that Echinacea has “…no
known toxicity” and gives the herb four stars in the category of safety
where it rates each herb that it evaluates.
The summary of the safety goes into great detail that people with
“auto-immune disorders such as tuberculosis, leicosis, connective
tissue disorders, collagenosis and related diseases such as lupus, according
to the German Kommission E” should not use the product.
As the article continues, it says that whether or not AIDS patients
should take Echinacea is still controversial.
The Truth: Scientific
Several studies have been conducted to determine whether or not the
herb, Echinacea, really works. “Ineffectiveness
of Echinacea for Prevention of Experimental Rhinovirus Colds” (Turner,
Riker, & Gangemi, 2000) is a study where the participants took 300mg of
Echinacea or a placebo three times daily for two weeks.
They were then “challenged with a fifty percent tissue culture-
infective doses of rhinovirus type 23”.
The Echinacea was taken for five more days after the challenge.
In the Echinacea group, 44% of the subjects were infected whereas 57%
of the placebo group were infected. The
scientists concluded that the effects were not significant thus stating that
Echinacea had no effect on the patients.
“A Randomized Controlled
Trial of the Effect of Fluid Extract of Echinacea Purpurea on the Incidence
and Severity of Colds and Respiratory Infections” (Grimm & Miller, 1999)
was the next double-blind study examined.
The people chosen for the study were ones who had three colds or
respiratory infections in the past year.
One hundred nine people were chosen to participate.
They were put into two groups. One
group took 4mL of Echinacea while the other took 4mL of a placebo two times a
day for two months. During the
eight weeks, 65% of the patients taking Echinacea had at least one cold or
upper respiratory infection while 74% of the placebo group developed an
ailment. People in both groups
also reported side effects; 20% of the Echinacea group and 13% of the placebo
group. Again the scientists
decided that the herb did not significantly alter the outcome of the events.
Echinacea Root Extracts for the Prevention of Upper Respiratory Tract
Infections: A Double-Blind,
Placebo- Controlled Randomized Trial” (Melchart, Walther, Linde, Brandmaier,
& Lersch 1998) was the next study with conclusive evidence sought. Three hundred two people with no illnesses took either
Ethanolic extract from Echinacea purpurea, Echinacea angustifolia, or a
placebo for twelve weeks “to investigate the safety and efficacy of 2
extracts of Echinacea for preventing upper respiratory tract infections”. The element that was being measured was the time until the
first infection. The results were
66 days for Echinacea angustifolia, 69 days for Echinacea purpurea, and 65
days for a placebo. Therefore the
research was thought to be insignificant enough to make any positive claims
about the herb.
A review written by Karen Gunning included the evaluation of a total of
twenty-six different clinical trials. She
found that only six of them used Echinacea as the only tested material and
only three trials evaluated the usage and prevention of the upper respiratory
tract infections. Two studies
were conducted by Braunig et al., which were designed to determine the effects
of both the Echinacea pallida root and the Echinacea purpurea root in the
treatment of acute respiratory tract infections.
A total of 160 participants were chosen for the first trial.
Patients took 900mg a day of either the Echinacea pallida or a placebo
to compare the length of the infection. The
Echinacea patients had illnesses averaging about 9.8 days while the placebo
patients had an average of 13 days. The
second study consisted of 180 people who took either 450mg of Echinacea
purpurea, 900mg of Echinacea purpurea, or a placebo.
The results were that the ones taking the placebo or the 450mg had
colds for about 8-10 days while the 900mg group only lasted 3-4 days.
Therefore the scientists determined that the effects of Echinacea are
dose dependent. Melchart and his
colleagues (as discussed in the previous paragraph) performed the final study
reviewed. They tested patients
with either 50 drops of ethanolic extracts of Echinacea purpurea, Echinacea
angustifolia, or a placebo. It
was administered two times a day five days a week for twelve weeks (this type
of study is called a three armed randomized double-blind trial).
Gunning did not report the results but just commented that the time
measured to develop an upper respiratory tract infection held no significance
from one treatment to another. Her
conclusion after studying the trials was that the drug is safe yet the
appropriate dosage and exact makeup of the herb is yet to be determined.
A study with more positive results is called “The Efficacy of
Echinacea Compound Herbal Tea Preparation on the Severity and Duration of
Upper Respiratory and Flu Symptoms: A
Randomized Double-Blind Placebo-controlled Study”.(Lindenmuth, 2000).
They gave their ninety-five subjects 5-6 cups of Echinacea Plus.
Each participant already had symptoms of infections of either colds or
flu. After two weeks, a
questionnaire was given to the patients asking about the efficacy, the number
of days the symptoms lasted, and the number of days it took for a change to
occur. The entire study lasted
for three months. The Echinacea
group but not the placebo group reported a significant effect.
Therefore, the researchers decided “treatment with Echinacea Plus tea
at early onset of cold or flu symptoms was effective for relieving these
symptoms in a shorter period of time than a placebo.”
Bruce Barrett, Monica Vohmann, and Carlo
Calabrese wrote a review called “Echinacea for Upper Respiratory Infection”
which looked at thirteen different Echinacea blinded placebo-controlled
randomized trials. Nine of them
were evaluating Echinacea as a treatment product and four of them as a
prevention product. Of the ones
looked at, eight had mainly positive results while three of the prevention
trials showed some significant effect. Therefore
the authors conclude that at an early stage, an infection with little severity
may be treated with Echinacea. The
researches found however that the herb is found with different elements added
into the compound with the different manufacturers.
There is no set dosage for the product.
Both of these unclear variables make it hard to determine whether or
not it is beneficial to take the herb.
Giles, Palat, Chien,
Chang, and Kennedy examined twelve studies ranging from 1961 to 1992. Six of them were treatment trials while the other six were
for both treatment and prevention. Although
eleven of the research teams concluded that their studies proved the
effectiveness of Echinacea, this review team found only one that was actually
based on methodological evidence. The
studies “lacked defined upper respiratory tract infection diagnostic
criteria, adequate sample sizes, randomization, description of the
randomization process, analysis of baseline subject, comparability,
descriptions of treatment interventions, defined outcome criteria, patient
blinding, evaluator blinding, and numbers of and reasons for subject
withdrawal.” Therefore the team researched another thirteen trials, which
had randomization and were double blind, placebo-controlled studies.
Eight of nine of the studies on the treatment had positive results
declaring the effectiveness of Echinacea.
The four prevention trials however proved to have insignificant
results. The reviewers also
concluded that there were few side effects but the herb has yet to be approved
for infants and children.
information posted on the Internet is an extremely important and sometimes
difficult task. When dealing with
health issues however, it is essential that research be done on the topic
further than just reading what advertising manufacturers want the public to
know or believe. Echinacea is an
herb that has yet to be approved by the FDA yet is commonly found and sold in
supermarkets, drug stores, and online. Companies
advertise whatever information they want about the product whether it is true
or not. Accurately referenced
material is not always included on web sites and should be looked at
hesitantly. Luckily on each of
the advertisements is a disclaimer declaring, “This statement has not been
evaluated by the Food and Drug Administration.
This product is not intended to diagnose, treat, cure, or prevent any
disease”. These two sentences
although extremely tiny and easy to overlook could alone sway buyers to look
into more in depth studies of the herb.
studies and reviews were placed on this web page to provide consumers with
this type of information. Despite all the research and the duration of
Echinacea, inconclusive results still remain about whether or not the drug
works. From researching the
studies, the best time to take a form of Echinacea would be at the start of an
ailment such as a cold or and acute upper respiratory infection to lessen the
severity of the symptoms and length that they last.
Vohmann, M., Calabrese, C. (1999).
Echinacea for Upper Respiratory Infection.
The Journal of Family Practice,
Palat, C., Chien, S., Chang, Z. Kennedy, D.
(1999). Evaluation of
Echinacea for Treatment of the Common Cold.
Miller, H. (1999).
A Randomized Controlled Trial of the Effect of Fluid Extract of
Echinacea Purpurea on the Incidence and Severity of Colds and Respiratory
Infections. The American Journal of Medicine, 106, 2
(1999). Echinacea in the
Treatment and Prevention of Upper Respiratory Tract Infections.
Western Journal of Medicine,
G., Lindenmuth, E. (2000). The Efficacy of Echinacea Compound Herbal Tea Preparation on
the Severity and Duration of Upper Respiratory and Flu Symptoms:
A Randomized, Double-Blind Placebo-controlled Study.
of Alternative and Complementary Medicine,6,
D., Walther, E., Linde, K., Brandmaier, R., Lersch, C.
(1998). Echinacea Root Extracts for the Prevention of Upper Respiratory
Tract Infections: A Double-Blind,
Placebo-Controlled Randomized Trial. Archives of Family Medicine,
Use of Echinacea in Medicine. Biochemical
Pharmacology, 60, 155-158
Turner, R., Riker, D., Gangemi, D. (2000). Ineffectiveness of Echinacea for Prevention of Experimental Rhinovirus Colds. Antimicrobial Agents and Chemotherapy, 44, 1708-1709
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