THE HISTORY OF ECHINACEA
The genus Echinacea (coneflower, family Asteraceae) is a common plant found in the central and eastern art of United States. The two main medicinal herbs used in Australia are the Echinacea angustifolia (regarded as the more potent plant) and the Echinacea purpurea species. It was widely used by the Native Americans and later by the white settlers for infections and ‘blood cleansing’.
MEDICAL USES OF ECHINACEA
Immune Boosting Effects
Antibiotics kill bacteria by directly damaging their cellular membrane, resulting in their death. This is why viruses are not affected by antibiotics as they do not have cellular membranes. Unlike antibiotics however, Echinacea kills bacteria and viruses by booting the bodies own immune system to destroy the invaders.
Studies have been done to examine the effect of Echinacea on the immune system, either by adding it to extracted white blood cells (our immune cells) or giving it to humans and then extracting the white blood cells. These studies demonstrate an increase in white blood cell activity and bacteria killing activity against staphylococcus infection. Increased production of other immune boosting chemicals (tumour necrosis factor and interleukin (IL)-6 and IL-1) has also seen. Another study showed that extracted white blood cells responded to application of Echinacea purpurea juice by producing more immune boosting chemicals (tumour necrosis factor, IL-6, and IL-1.) The extracts from Echinacea, when applied to immune cells resulted in an increase of the overall killing ability of the white blood cells.
Echinacea for Infections
A number of studies have been conducted to assess the efficacy of various Echinacea products to treat and prevent upper respiratory tract infections (URIs) in adults. The results of critical reviews of these studies indicate that the evidence for the efficacy of Echinacea as a treatment in adults is fairly strong. Of the published Echinacea prevention studies in adults, at least six included a placebo control group (making the study more valid). The results of these prevention trials suggest a 12%–20% reduction in the subsequent occurrence of upper respiratory infections after Echinacea treatment. 
One recent study found that Echinacea purpurea may help to prevent colds and flu in kids. The results of this study suggested that Echinacea purpurea, when taken as a treatment for an initial upper respiratory
tract infection, may be effective in preventing subsequent upper respiratory tract infections. In this secondary analysis of data from a randomized controlled treatment trial, children that received Echinacea treatment had a risk of subsequent upper respiratory tract infections that was 28% lower than children assigned to receive placebo. A decrease of this magnitude in the number of upper respiratory tract infections per year could have a large public health impact, given that up to 40% of visits to pediatricians in the winter months by children 1–5 years old are because of cough and URI symptoms. 
Graph 1. The above graph shows that almost twice as many children taking Echinacea avoided a secondary Upper Respiratory Infection (URI) that the children on the placebo. 
CONTRAINDICATIONS OF ECHINACEA
Echinacea is generally regarded as a safe herb however it should be avoided during pregnancy unless professionally prescribed. Boosting certain aspects of the immune system during pregnancy can lead to certain complications. Although the adverse effect profile and tolerability of this herb are excellent, long-term safety studies are lacking. Check with your health care practitioner before taking this herb long term.
Higher dosages may be contradicted in some individuals suffering from inflammatory conditions where the immune system is already overactive (such as Arthritis). Again, please speak to your practitioner about the suitability of this herb for you.
DRUG INTERACTIONS WITH ECHINACEA
Although Echinacea, like any herbal medicine, can conflict with medications, no significant herb/drug interactions with Echinacea have been reported. As a precaution it is advised that before using this herb or any other herbal preparation, to consult your health care professional.
THERAPEUTIC/SAFE DOSAGES OF ECHINACEA
For freeze-dried extract, the dosage is 1 to 2 capsules three times per day. For dry powdered extract (standardized to 3.5% echinacoside), 300 mg three times per day. If you are using a liquid extract (1:1), 1/4 to 1/2 teaspoon three times daily is suitable. For the dried root or tea, 0.5 to 1 g three times per day is an ideal dosage.  A qualified herbalist may prescribe higher dosages for acute infections.
Studies have found that short and long term consumption is beneficial for the treatment and prevention of infections. It is advised that you take Echinacea at the first sign of a cold or flu. Alternatively, taking a lower dose over a few months during winter will also benefit your immune system.
OTHER HERBS THAT CAN BE USED WITH ECHINACEA
As with many herbal preparations, herbs are often combined to make a formula. This formula usually contains herbs with a similar action thus improving the effectiveness over a single herbal preparation. Herbs that are commonly found with Echinacea for the treatment of infections include:
- Golden Seal. This is a great herb for drying mucus and also boosting ones immune system. Golden Seal increases similar, but different immune boosting chemicals in the body. It also directly kills infections in a similar way to antibiotics.
- Garlic. Best know for its pungent odour and pleasant taste, garlic is also one of natures best antibiotics. While Garlic kills microbes directly, it also has a wonderful immune stimulation effect.
- Astragalus. Astragalus benefits the immune system by firing up the white blood cells to kill microbes. Studies have also found that it reduces the effects of bacterial and viral infections including the flu and hepatitis, while also being beneficial for AIDS sufferers. Host herbalists recommend Astragalus for moderate to long term uses.
Echinacea is a highly prized herb and has been used for thousands of years for the treatment of infections illnesses. Clinical trials now support these uses and there is weighty scientific data that supports the medicinal uses of this herb. While Echinacea is generally regarded as safe, interactions between this herb and medical drugs are possible. If you are on medication of any kind, please check with your health care professional before taking any herbs.
1. Association, A.H., Whole Foods. Herb Products Sales. American Herb Association, 2002. Quarterly Newsletter(7).
2. Blumenthal, M., Herb sales down 15 percent in mainstream
market. HerbalGram, 2001. 69.
3. A., T., Echinacea juice for immune stimulation: assessment of risks and benefits. American Botanical Council, 1997(Herb Clip No. 100874).
4. Bauer, R., Echinacea: biological effects and active principles, in Lawson L, Bauet R (eds): Phytomedicine of Europe: Chemistry and Biological Activity. American Chemical Society, 1998: p. 140–157.
5. Roesler J, E.A., Steinmuller C, et al., Application of purified polysaccharides from cell cultures of the plant Echinacea purpurea to test subjects mediates activation of the phagocyte system. Int J Immunopharmacol, 1991. 13: p. 931–941.
6. Burger R, T.A., Warren R, et al., Echinacea-induced cytokine production by human macrophages. Int J Immunopharmacol, 1997. 19: p. 371–379.
7. Graisbauer M, S.T., Stickl H, et al., The effect of Echinacea purpurea Moench on phagocytosis in granulocytes measured by chemiluminescence. Arzneimittelforschung, 1990. 40: p. 594–598.
8. Weber W, T.J., Stoep AV, Weiss NS, Standish LJ, Calabrese C., Echinacea purpurea for prevention of upper respiratory tract infections in children. J Altern Complement Med, 2005. 11(6): p. 1021-6.
9. Islam J, C.R., Use of Echinacea in upper respiratory tract infection. South Med J, 2005. 98(3): p. 311-8.
The information contained on this website is for educational purposes only. It is not provided to diagnose, prescribe or treat any condition of the body. The information on this website should not be used as a substitute for medical counselling with a health professional.