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Kelly McCoy’s

The Hype & The Truth About…



* What is it?

* History                             

* The Hype: What’s On the Internet

* How does it really work?

* Side effects

* The Truth: Scientific Studies

* Conclusion

* Works Cited



What is it?                                                   


          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. (





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 (



The 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.


How Does It Really Work?


          Health 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.

Side Effects


            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 provides is to “Keep out of reach of children”. only warns to “not use this product if pregnant or nursing”.  Medical 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.

The Herb 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 Studies



          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.





Evaluating 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. 

Several 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.




Works Cited


Barrett, B, Vohmann, M., Calabrese, C.  (1999).  Echinacea for Upper Respiratory Infection.  The Journal of Family Practice, 48, 8.


Giles, J., Palat, C., Chien, S., Chang, Z. Kennedy, D.  (1999).  Evaluation of Echinacea for Treatment of the Common Cold.  Pharmacotherapy, 20, 6


Grimm, W., 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


Gunning, K.  (1999).  Echinacea in the Treatment and Prevention of Upper Respiratory Tract Infections.  Western Journal of Medicine, 171, 3


Lindenmuth, 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.  The Journal of Alternative and Complementary Medicine,6, 327-334


Melchart, 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, 7,6


Percival, S.  (2000)  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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