Echinacea

Also listed as: Echinacea angustifolia; Echinacea pallida; Echinacea purpurea; Purple coneflower


Overview

One of the most popular herbs in America today is the Native American medicinal plant called echinacea. Named for the prickly scales in its large conical seed head, the herb resembles the spines of an angry hedgehog (echinos is Greek for hedgehog).

Results of archeological digs indicate that Native Americans may have used echinacea for more than 400 years to treat infections and wounds and as a general "cure-all." Throughout history people have used echinacea to treat scarlet fever, syphilis, malaria, blood poisoning, and diphtheria. Although this herb was popular during the 18th and 19th centuries, its use began to decline in the United States after the introduction of antibiotics. Echinacea preparations became increasingly popular in Germany throughout the 20th century. In fact, most of the scientific research on echinacea has been conducted in Germany.

Today, people use echinacea to shorten the common cold and flu and reduce symptoms, such as sore throat (pharyngitis), cough, and fever. Many herbalists also recommend echinacea to help boost the immune system and help the body fight infections.

General Uses

Several laboratory and animal studies suggest that echinacea contains active substances that enhance the activity of the immune system, relieve pain, reduce inflammation, and have hormonal, antiviral, and antioxidant effects. For this reason, professional herbalists may recommend echinacea to treat urinary tract infections, vaginal yeast (candida) infections, ear infections (also known as otitis media), athlete's foot, sinusitis, hay fever (also called allergic rhinitis), as well as slow-healing wounds.

Common Cold

Whether or not echinacea helps prevent or treat the common cold remains under debate. Some studies have shown that the herb can make you feel better faster; others suggest that echinacea has no impact on a cold at all. Several trials have shown that people who take echinacea as soon as they feel sick reduce the severity of their cold and have fewer symptoms than those who do not take the herb. One study of 95 people with early symptoms of cold and flu (such as runny nose, scratchy throat, and fever), found that those who drank several cups of echinacea tea every day for 5 days felt better sooner than those who drank tea without echinacea.

However, a rigorous study published in 2005 in the New England Journal of Medicine determined echinacea does not help to prevent or treat colds. Researchers compared the effects of echinacea angustifolia root to placebo on 437 volunteers before and after they were exposed to cold viruses. Volunteers who took echinacea were just as likely to catch a cold and had as severe symptoms as those who received placebo.


Plant Description

Echinacea has tall stems, bears single pink or purple flowers and has a central cone that is usually purplish-brown in color. The large cone is actually a seed head with sharp spines that resemble a stiff comb. Of nine echinacea species, only three are used for medicinal purposes ( Echinacea angustifolia , Echinacea pallida , and Echinacea purpurea ).


What's It Made Of?

Echinacea contains several chemicals that play a role in its therapeutic effects. These include polysaccharides, glycoproteins, alkamides, volatile oils, and flavonoids.

The chemicals contained in the root differ considerably from those in the upper part of the plant. For example, the roots have high concentrations of volatile oils (odorous compounds) while the above-ground parts of the plant tend to contain more polysaccharides (substances known to trigger the activity of the immune system). The combination of these active substances is responsible for echinacea’s beneficial effects, though research suggests that the above ground portion of Echinacea purpurea is the most effective.

In Germany (where herbs are regulated by the government), the above-ground parts of Echinacea purpurea are approved to treat colds, upper respiratory tract infections, urinary tract infections, and slow-healing wounds. The root of the Echinacea pallida plant is also approved for the treatment of flu-like infections. Many echinacea products available in the United States contain one, two, or even all three plant species.


Available Forms

Three species of echinacea are commonly used for medicinal purposes: Echinacea angustifolia , Echinacea pallida , and Echinacea purpurea . Many echinacea preparations contain one, two, or even all three of these species. Different products use different parts of the echinacea plant. This is why some experts believe the effectiveness of echinacea differs from one product to another.

Echinacea (including one, two, or all three species) is available in extracts, tinctures, tablets, capsules, and ointments. It is also available in combination with other immune-boosting herbs, vitamins, and minerals.

A study performed by ConsumerLab.com (an independent company that tests the purity of health, wellness, and nutrition products) found that of 11 brands of echinacea purchased for testing, only 4 contained what was stated on their labels. About 10 % had no echinacea at all; half were mislabeled as to the species of echinacea in the product; and more than half of the standardized preparations did not contain the labeled amount of active ingredients. Buy products made by reputable, established companies that distribute their products through trustworthy and knowledgeable establishments. When possible, select products with guaranteed potency or standardized extracts.


How to Take It

Pediatric

Adjust the recommended adult dose to account for the child's weight. Most herbal dosages for adults are calculated on the basis of a 150 lb (70 kg) adult. Therefore, if the child weighs 50 lb (20 to 25 kg), the appropriate dose of echinacea would be 1/3 of the adult dose.

Use alcohol-free preparations for children.

Adult

For general immune system stimulation, during colds, flu, upper respiratory tract infections, or bladder infections, choose from the following forms and take three times a day:

For slow-healing wounds, creams or ointments should be applied as needed.


Precautions

The use of herbs is a time-honored approach to strengthening the body and treating disease. However, herbs contain active substances that may trigger side effects and interact with other herbs, supplements, or medications. For these reasons, people should take herbs under the supervision of a practitioner knowledgeable in the field of botanical medicine.

The American Herbal Products Association gives echinacea a class 1 safety rating, which means that it is safe when used appropriately (as instructed by the product label) and with the guidance of a healthcare professional. In Germany, use of echinacea is restricted to no longer than eight weeks at a time. Since echinacea loses its effectiveness after eight consecutive weeks regular users of this herb, need "break" periods -- periods of time that they are not taking echinacea -- in order to enhance immune function and fight infection.

People with tuberculosis, leukemia, diabetes, connective tissue disorders, multiple sclerosis, HIV or AIDS, any autoimmune diseases, or, possibly, liver disorders should not take echinacea. There is some concern that echinacea may reduce the effectiveness of medications that suppress the immune system. For this reason, people receiving organ transplants who must take immunosuppressant medications should avoid this herb. (See Possible Interactions. )

In rare cases, echinacea may cause allergic reactions ranging from a mild rash to anaphylaxis (a life threatening reaction accompanied by throat tightening, shortness of breath, and, possibly, fainting). People with asthma and allergies may be at an increased risk for developing these adverse reactions.

There has been one report of an individual developing erythema nodosum (a painful skin condition) after taking echinacea to treat the flu.

When taken by mouth, echinacea may cause temporary numbing and tingling on the tongue.

Despite concerns that echinacea may be unsafe for pregnant or breastfeeding women, evidence suggests that the use of echinacea during pregnancy does not increase the risk of birth defects or other pregnancy-related health problems.  


Possible Interactions

If you are taking any of the following medications, you should not use echinacea without first talking to your healthcare provider:

Econazole echinacea may be useful in combination with econazole, an antifungal agent used to treat yeast infections (such as athlete's foot). When echinacea is used together with econazole, recurrence rates of these infections may be reduced.

Immunosuppressants Immunosuppressants refers to a group of medications that are used for two main purposes -- treat cancer and suppress the immune system following organ transplant so that the new organ is not rejected. Because echinacea can enhance immune function, people should not use the herb with immunosuppressive medications, especially when taken for organ transplant.

In terms of cancer treatment, a couple of test tube studies imply that echinacea may be useful when used in combination with cyclophosphamide, one medication in this class. Using echinacea with this or other chemotherapy agents that act as immunosuppressants, may allow the cancer-fighting medicines to kill the tumors while still protecting the immune system. If this theory proves to be correct then echinacea could possibly prevent many of the side effects of chemotherapy.


Supporting Research

Ang-Lee M, Moss J, Yuan C. Herbal medicines and perioperative care. JAMA . 2001;286(2):208-216.

Barrett B, Kiefer D, Rabago D. Assessing the risks and benefits of herbal medicine: an overview of scientific evidence. [Review]. Altern Ther Health Med . 1999;5(4):40-49.

Barrett B, Vohmann M, Calabrese C. Echinacea for upper respiratory infection. J Fam Pract . 1999;48:628-635.

Blumenthal M, Goldberg A, Brinckmann J. Herbal Medicine: Expanded Commission E Monographs . Newton, MA: Integrative Medicine Communications; 2000:88-102.

Borchers AT, Keen CL, Stern JS, Gershwin ME. Inflammation and Native American medicine: the role of botanicals. [Review]. Am J Clin Nutr . 2000 Aug;72(2):339-347.

Brinkeborn RM, Shah DV, Degenring FH. Echinaforce and other Echinacea fresh plant preparations in the treatment of the common cold. A randomized, placebo controlled, double-blind clinical trial. Phytomedicine . 1999;6(1):1-6.

Brinker F. Herb Contraindications and Drug Interactions . 2nd ed. Sandy, OR: Eclectic Medical Publications; 1998:67-69.

ConsumerLab.com. Product review: echinacea. Accessed at: http://www.consumerlab.com/results/echinacea.asp on April 1, 2002.

Ernst E. The risk-benefit profile of commonly used herbal therapies: Ginkgo, St. John's Wort, Ginseng, Echinacea, Saw Palmetto, and Kava. [Review]. Ann Intern Med . 2002;136(1):42-53.

Frank LG. 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. J Comp Alt Med . 2000;6(4):327-334.

Gallo M, Sarkar M, Au W, et al. Pregancy outcome following gestational exposure to echinacea. Arch Intern Med . 2000; 160:3141-3143.

Lindenmuth GF, Lindenmuth EB. 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. J Altern Complement Med . 2000;6(4):327-334.

Mahady GB. Echinacea: recommendations for its use in prophylaxis and treatment of upper respiratory tract infections. Nutr Clin Care . 2001;4(4):199-208.

Melchart D, Walther E, Linde K, Brandmaier R, Lersch C. Echinacea root extracts for the prevention of upper respiratory tract infections: a double-blind, placebo-controlled randomized trial. Arch Fam Med . 1998;7:541 – 545.

Melchart D, Linde K, Fischer P, Kaesmayr J. Echinacea for preventing and treating the common cold. [Review]. Cochrane Database Syst Rev . 2000;(2):CD000530.

Melchart D, Linde K, Worku F, Sarkady L, Holzmann M, Jurcic K, et al. Results of five randomized studies on the immunomodulatory activity of preparations of echinacea. J Alt Comp Med . 1995;1(2):145 – 160.

Miller LG. Herbal medicinals: selected clinical considerations focusing on known or potential drug-herb interactions. Arch Intern Med . 1998;158(20):2200 – 2211.

Mullins RJ, Heddle R. Adverse reactions associated with echinacea: the Australian experience. Ann Allergy Asthma Immunol . 2002;88(1):42-51.

O'Hara M, Kiefer D, Farrell K, Kemper K. A review of 12 commonly used medicinal herbs. Arch Fam Med . 1998;7(6):523-536.

Percival SS. Use of echinacea in medicine. [Review]. Biochem Pharmacol . 2000;60(2):155-158.

Rotblatt M, Ziment I. Evidence-Based Herbal Medicine . Philadelphia, PA: Hanley & Belfus, Inc; 2002:160-165.

Soon SL, Crawford RI. Recurrent erythema nodosum associated with Echinacea herbal therapy. J Am Acad Dermatol . 2001;44(2):298-299.

Turner RB, Riker DK, Gangemi JD. Ineffectiveness of Echinacea for prevention of experimental rhinovirus colds. Antimicrob Agents Chemother . 2000;44:1708-1709.

White L, Mavor S. Kids, Herbs, Health . Loveland, Colo: Interweave Press; 1998:22, 28-29.


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