Botanical Name: Echinacea angustifolia, Asteraceae

Common name: Echinacea, Purple Cone Flower, Narrow-leaved Coneflower

Similar species: E. purpurea, E. pallida

Plant description: Echinacea is a herbaceous perennial, with a slender stem bristling with hairs, 50-180 cm in height, arising from thick, black roots. The leaves are 3-veined and vary in shape from lanceolate to linear, slender at the base, the lowermost leaves with short petioles. The flower head consists of white, pink or purple ray florets that fringe a conical disk of tubular florets that give way to a four sided achenes. All taxa within the genus Echinacea hybridize, and thus hybrids within this genus are common.

Habitat, ecology and distribution: The range for Echinacea extends from western Minnesota to eastern Saskatchewan southwards, east of the Rocky Mountains, to Texas, occurring in greatest concentration on the Great Plains.  In prefers open dry forest and grasslands, its presence an indicator of good range for livestock.  Recent drought conditions, overgrazing and over-harvesting has had a serious impact on wild populations, and E. angustifolia is currently on the United Plant Savers "at risk" list (www.unitedplantsavers.org), and in some states unauthorized harvesting is a punishable offense.  At this time the amount of E. angustifolia under cultivation does not appear to meet the market demand, and thus can be a little more difficult to obtain in very large quantities.

Part used: Roots, seeds, leaf.  Commercial sources may be adulterated with other members of the Asteraceae, especially Parthenium integrifolium (Bauer & Foster, 1989).

History: Although Echinacea has grown to become one of the most popular herbs of commerce, it is perhaps interesting to note that its therapeutic indications over the years have changed to a considerable degree.  The earliest usage of Echinacea resides in the First Nations healing tradition, which reportedly used it in the treatment of venomous bites and stings, as a mouth rinse for sore throat and tonsillitis, in the treatment of infected ulcers and sores, and in the treatment of gastrointestinal illness (Willard 1992, 211). Felter and Lloyd state that Echinacea was introduced into modern clinical practice by a Dr. H. F. C. Meyer, of Pawnee City, Nebraska, who marketed it under the name "Meyer's Blood Purifier" (1893). Following what appears to be a reflection of historical usage, Meyer claimed that it was an antidote for insect stings and in particular the bite of the rattlesnake. Among its other uses indicated by Meyer were malaria, cholera, internal abscesses, typhoid fever, ulcers, herpetic lesions, boils, sore throat, respiratory congestion, hemorrhoids, eczema, acne, headache and ophthalmic disorders (Felter and Lloyd 1893).  Although the Eclectics had a somewhat more cautious approach, they found that many of Meyer's claims could be substantiated, and John King especially was impressed by it, and included it in his Dispensatory. 

There has been for some time confusion surrounding the different species of Echinacea, and whether or not they contain the same properties. This confusion begins with German homeopaths that imported what they thought was Echinacea angustifolia during the late 1800's, but what was in fact classified as another species called Rudbeckia purpurea (now E. purpurea).  In later scientific studies with Echinacea, some German researchers obtained what they thought was E. angustifolia but was in fact E. pallida.  With this latter confusion much of the German research on E. angustifolia before 1987 may be in fact data for E. pallida, and should be viewed with caution (Bradley 1992, 81).

Constituents: Although some of the data on the various Echinacea species may be confused, it appears that many constituents can be found in all three major species (e.g. angust., purp., pall.).  One of the most characteristic constituents of Echinacea are the akylamides.  These are mostly comprised of isobutylamides that provide for the characteristic tingling sensation felt in the mouth upon ingestion, a constituent said to be highest in E. pallida.  Other constituents found in the root include caffeic acid esters, primarily echinacoside, as well as chicoric acid (E. purpurea only) and cynarin (E. angustifolia only).  The root has also been shown to contain an essential oil, polyacetylenes, polysaccharides, phytosterols and non-toxic pyrrolizidine alkaloids.  Both the seeds and the leaf contain a similar range of constituents as the root, but also contain flavonoids (Mills and Bone 2000, 356; Bradley 1992, 81)

Medical Research: Echinacea has undergone a significant amount of experimental investigation since the 1950's, much of which has led to the current view of it as an antimicrobial and antiviral agent, with immunostimulatory and anti-inflammatory properties.  Unfortunately most of this research is based upon in vitro models, or in vivo models that use isolated constituent extracts, often injected into the bloodstream of experimental animals. The primary observations made in these studies, many of them involving the activity of the purified polysaccharides (which are precipitated in tincture and inert), include an increase in non-specific and immune-specific activities, e.g. inhibition of hyaluronidase, cytokine activation (e.g. IL-1), leukocyte migration, phagocytic enhancement, an increase in T-lymphocytes activity (with a shift of the T4/T8-cell ratio in favor of T4 cells), and viral inhibition  (Mills and Bone 2000, 357; Schoneberger 1992). As useful as this information is, it does not provide any real understanding of how an oral dose of Echinacea exerts its effect in the human body.  Mills and Bone mention that the only effect that has been noted in experimental oral doses is a non-specific enhancement of immunity (2000, 357).

One of the more common misconceptions of Echinacea is that its immunostimulant properties wear off after a period of weeks if taken on a regular basis.  Thus one recommendation suggests that Echinacea doses should be pulsed, taken for 10 days on, five days off, etc.  This is based on an English mistranslation of the original German study by Jurcic et al published in 1989.  In the original article, the study shows that the Echinacea-induced elevation of phagocytosis begins to decline after day five and levels off from day eight to ten. However, the dose of Echinacea used in the study was discontinued after day five, a fact that was missing from the English translation.  Thus instead of showing a diminished response to Echinacea over ten days, the study appears to indicate that there is an elevation of phagocytosis for five days after the Echinacea was discontinued (Bergner 2001, 115; Jurcic et al 1989).  There have been a few clinical studies with Echinacea, mostly very preliminary, looking at its measured effect in clinical trials of cold and flu symptoms.  The majority of these studies show a benefit for Echinacea, especially if taken at the very early stages of a cold or flu.  There are almost as many studies however that show no statistical benefit in taking Echinacea when compared with placebo.  The problem may lie in poor quality control in the market place, and thus it is difficult to come to any sort of conclusion on any of the studies.  The following are a few examples of the clinical studies that have been conducted so far:
•Cold and flu symptoms:A randomized, double-blind, placebo-controlled community-based trial examined the efficacy of an encapsulated mixture of unrefined Echinacea purpurea herb (25%) and root (25%) and E. angustifolia root (50%), taken in 1-g doses six times on the first day of illness and three times on each subsequent day of illness for a maximum of 10 days.  The results indicated no statistically significant difference between the Echinacea and placebo groups for any of the measured outcomes (Barrett et al 2002).  A randomized, double-blind, placebo-controlled clinical trial of 80 men and women examined the efficacy Echinaceae purpurea herb (Echinacin, EC31J0) in reversing cold symptoms. In the Echinacea group the median time of illness was 6.0 days compared to 9.0 days in the placebo group. EC31J0 was well tolerated and clinically effective in alleviating symptoms more rapidly than placebo in patients with a common cold (Schulten 2001). A random double-blind placebo-controlled study examined the efficacy of an Echinacea compound herbal tea preparation (Echinacea Plus) given at early onset of cold or flu symptoms in 95 subjects.  Researchers noted a significant difference between the experimental group and control group, suggesting that Echinacea at early onset of cold or flu symptoms was more effective than a placebo (Lindenmuth et al 2000). Patients attending one of 15 study practitioners as a result of acute symptoms of the common cold were enrolled in a randomized double-blind placebo-controlled study of a preparation of Echinacea root, Baptisia root and Thuja occidentalis, 3 tabs t.i.d. for 7 to 9 days. In all, 259 patients were evaluated, the results indicating the superiority of the herbal remedy over placebo.  In the subgroup of patients that started therapy at an early phase in their cold symptoms the efficacy of the herbal remedy was most prominent.  The therapeutic benefit of the herbal remedy was found to occur by day 2 and attained its greatest significance on day 4, continuing until the end of the treatment (Henneicke-von Zepelin 1999).
•Antineoplastic: Mills and Bone report two clinical studies that looked at the efficacy of Echinacea (E. angustifolia and E. pallida) in combination with Baptisia and Thuja in the treatment of breast cancer, in conjunction with chemoradiation therapy.  Overall, this combination showed some benefit, promoting the recuperation of the hematopoietic system and reducing the incidence of infection, when compared with controls (2000, 359).

Toxicity: Echinacea has displayed no demonstrable toxic effects (Mills and Bone 2000, 359).

Herbal action: alterative, immunostimulant, antimicrobial, antiviral, immunomodulant, anti-inflammatory, lymphatic, vulnerary

Indications: acute fever; chronic catarrhal conditions, including sinus congestion, lymphatic congestion, pharyngitis, and bronchitis; septic conditions (topically and internally); abdominal pain made worse by eating, with bad breath; acne, boils, eczema; pain, in cancer; acute injuries, venomous bites and sting; immunodeficiency

Contraindications and cautions: Mills and Bone describe an immunomodulant property for Echinacea, suggesting that it 'modulates' rather than stimulates the immune system.  In particular, Mills and Bone argue that the contraindication for autoimmune disease described in the GermanCommission E monographs is not supported by any clinical studies (2000, 359).  Even still, anecdotal evidence suggests that Echinacea can promote adverse effects in some patients with autoimmune disease, although this effect may not be noted in all.  Thus, Echinacea should be used with caution in autoimmune disease.  The use of Echinacea in acquired immunodeficiency states however, also contraindicated in the Commission Emonographs (Blumenthal et al 1996), does not meet with the experience of many herbalists who continue to use it to treat any opportunistic infection.

Medicinal uses: King's American Dispensatory contains a rather large and enthusiastic entry on Echinacea, John King singling it as the primary corrector of "depraved fluids," what in an earlier period was referred to as 'bad blood,' evidenced by a tendency to sepsis, malignant ulcers, and foul smelling discharges.  Felter and Lloyd write about "äits extraordinary powersãcombining essentially that formerly included under the terms antiseptic, antifermentative, and antizymoticãare well shown in its power over changes produced in the fluids of the body, whether from internal causes or from external introductions. The changes may be manifested in a disturbed balance of the fluids resulting in such tissue alterations as are exhibited in boils, carbuncles, abscesses, or cellular glandular inflammations. They may be from the introduction of serpent or insect venom, or they may be due to such fearful poisons as give rise to malignant diphtheria, cerebro-spinal meningitis, or puerperal and other forms of septicaemia. Such changes, whether they be septic or of devitalized morbid accumulations, or alterations in the fluids themselves, appear to have met their antagonist in echinacea. "Bad blood," so called, asthenia, and adynamia, and particularly a tendency to malignancy in acute and subacute disorders, seem to be special indicators for the use of echinacea" (1893).  Echinacea was especially indicated if these symptoms were accompanied weakness and emaciation, perhaps with a bluish or purplish coloration to the skin and mucous membranes.  The tongue might be covered in a dirty-brown coating, and the pulse will be thin and weak.

Supporting the First Nations usage of Echinacea, the Eclectics report that Echinacea has met with success in the treatment of acute injuries complicated by infection, and appeared to successfully treat venomous insect bites. Echinacea however is also mentioned in variety of other complaints, as in tonsillitis, with or without ulceration, as well catarrhal affections of the nose, sinuses, and naospharynx.  Similarly, Echinacea is said to be of benefit is chronic bronchitis, and was even used by the Eclectics to "…avert a gangrenous termination in pulmonic affections" (Felter and Lloyd 1893).  Echinacea is also thought to be helpful "fermentative dyspepsia," characterized a foul to fruity smelling breath as well as abdominal pain that is aggravated upon eating, especially foods such as flour products and commercial dairy. In fever, Echinacea is an important tool for parents, effectively helping resolve eruptive diseases such as measles, chicken-pox, and scarlet fever, also mentioned in typhoid and especially in malarial fever to control symptoms, but not periodicity. Felter and Lloyd state that influenza is partially ameliorated by Echinacea, used primarily to ensure "…good convalescence" (1893). Echinacea is also mentioned in the Eclectic literature as a remedy for pain, in the treatment of erysipelas, and especially in cancer for which its virtues are extolled by Eli Jones in his text Cancer: It's Causes, Symptoms and Treatment.  Jones states that Echinacea is indicated by the pain of cancer, but does not actually treat it.  King's states that this effect is best noted when the cancer involves the mucus membranes pain of cancerous growths, particularly when involving the mucous membranes. Echinacea is also used by herbalists as a remedy for the skin, and in particular the treatment of eczema, especially in chronic conditions with a wet, sticky exudate, and which the patients are thin and weak (Felter and Lloyd 1893).

Pharmacy and dosage:
•Fresh Plant Tincture: fresh root/seed 1:2, 95% alcohol, 20-60 gtt
•Dry Plant Tincture: recently dried root/seed, 1:5, 50% alcohol, 20-60 gtt, 1-10 mL
•Hot Infusion: recently dried leaf and flower, 1:20, 60-120 mL
•Decoction: recently dried root, 1:20, 60-120 mL
•Powder: recently dried root, 500-5000 mg

REFERENCES

Barrett BP, Brown RL, Locken K, Maberry R, Bobula JA, D'Alessio D. 2002. Treatment of the common cold with unrefined echinacea. A randomized, double-blind, placebo-controlled trial. Ann Intern Med. Dec 17, 137(12):939-46
Bauer, R. and S. Foster. 1989. HPLC Analysis of Echinacea simulata and E. paradoxa roots. Planta Medica. 55:637.
Bergner, Paul. 2001. Medical Herbalism: Materia Medica and Pharmacy. Boulder, CO: Bergner Communications.
Blumenthal, M., T. Hall, R. Rister, B. Steinhoff (eds.; S. Klein and R. Rister (trans). 1996. The German Commission E Monographs. Austin, TX: American Botanical Council.
Bradley, Peter R. ed. 1992. British Herbal Compendium. Bournemouth, UK: British Herbal Medicine Association.
Felter, HW and JU Lloyd. 1893. King's American Dispensatory. Digitized version available from http://www.ibiblio.org/herbmed/eclectic/kings/main.html.
Henneicke-von Zepelin H, Hentschel C, Schnitker J, Kohnen R, Kohler G, Wustenberg P. 1999. Efficacy and safety of a fixed combination phytomedicine in the treatment of the common cold (acute viral respiratory tract infection): results of a randomised, double blind, placebo controlled, multicentre study. Curr Med Res Opin. 15(3):214-27
Jurcic K, Melchart D, Holsmann M, Martin P, et al. "Zwei probandenstudien zur stimulierung der granulozyphagozytose durch echinacea-extract-haltige pr‰parate." Zeitschrift fˆr Phytotherapie. 10:67-70
Lindenmuth GF, Lindenmuth EB. 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. J Altern Complement Med Aug 6(4):327-34
Schulten B, Bulitta M, Ballering-Bruhl B, Koster U, Schafer M. 2001. Efficacy of Echinacea purpurea in patients with a common cold. A placebo-controlled, randomised, double-blind clinical trial. Arzneimittelforschung. 51(7):563-8
Weiss, Rudolf. 1988. Herbal Medicine. Translated by A.R. Meuss. Beaconsfield, England: Beaconsfield Publishers
Willard, Terry. 1992. Edible and Medicinal Plants of the Rocky Mountains and the Neighbouring Territories. Calgary: Wild Rose College of Natural Healing.