Herbal Remedies : Echinacea

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  • Herbal Remedies

    EchinaceaThe Cold and Flu Remedy

    Steven Foster

    Clinicians know the routine by now.Little Stevie is dragged into thedoctor's office by his mother, whopromptly rattles off a list of symptomsplaguing her son: fever, body aches, nasalcongestionthe usual constellation ofsymptoms signaling the onset of a cold orthe flu. As always, mother wants some-thing for her child, and demands anantibiotic to cure his condition. Of course,the doctor has given her the lecture beforeabout how antibiotics have no effect onviral syndromes. Somehow, she never lis-tens. With all the office visits resultingfrom the cold and flu season the clinicianwonders, in earnest, when the pharma-ceutical companies will come up with areally useful remedy. Sounding like a bro-ken record again, the beleaguered physi-cian repeats his age-old advice of fluids,rest, and something to reduce the fever.As the mother leaves the office with herson, feeling as though she has wasted hertime and money, the doctor wonders howmany more cold and flu cases he will seetoday.Patients with colds or flu are in an

    excellent position to take matters intotheir own hands with the helpful herbalremedy known as echinacea. A wild flow-er found only in North America, echi-nacea helps stimulate the immune systemto fight off infectious agents that causesymptoms in the body. When patientstake echinacea at the first onset of symp-toms, resolution of these symptoms is254

    often quick and effective. Echinacea offersa viable alternative to antibiotics forpatients who demand that the clinician dosomething. By educating their patientsabout echinacea, clinicians can help themtake control of their health and well-beingand reduce unnecessary and costly officevisits.

    When is Echinacea Useful?Echinacea is used to enhance or "stimu-

    late" the body's own resistance againstinfections, especially in the prevention ofcolds and flu. It is also used in patientswith strep throat, those with herpes, andeven patients with candidiasis, amongothers (see sidebar). Since the late 1970s, anumber of studies have explored theimmune system-stimulating potential ofechinacea preparations.1 Immunostimu-lants are agents that stimulate theimmune system in a nonspecific manner.The primary modern use for echinaceapreparations is as a nonspecific immuno-stimulant. An increase in phagocytosis(by macrophages and granulocytes) is animportant factor in immunostimulation.Nonspecific immunostimulatory actionfades relatively quickly and requiresrepeated dosage to sustain effect. If takenin small frequent doses at the onset ofsymptoms, every two to three hours forthe first two days, it often helps to mobi-lize the body's own resistance to infec-tions.2

    Recent research suggests that echinaceaworks best when taken at the onset of thefirst sign of symptoms of colds and flu.For acute conditions, use is best for a two-

    week period, followed by a one-weekresting period.3Contraindications Are ImportantThe term "immunostimulant" has often

    erroneously associated echinacea with con-ditions of impaired immune function.Echinacea is contraindicated in autoim-mune diseases. German clinical experienceshows that echinacea is contraindicated inconditions such as leukosis (involving anabnormal proliferation of white bloodcells), collagenosis (in which connectivetissues are attacked by the immune sys-tem, as in systemic lupus erythematosus),multiple sclerosis (which involves aheightened immune response), tuberculo-sis, diabetes mellitus, and AIDS.4

    Early History of UsageIn his classic ethnobotany of Indian

    groups of the Missouri River Valley, eth-nologist Melvin Gilmore wrote, "Echi-nacea [angustifolia] seems to have beenused as a remedy for more ailments thanany other plant."5 While known amongAmerican Native groups for centuries, thefirst written account of medicinal use ofE. angustifolia came relatively late. In an1887 article, eclectic physician John King,M.D., introduced E. angustifolia to themedical profession.6 In 1895, the firstechinacea products were produced byLloyd Brothers Pharmacists, Inc., ofCincinnati. By the turn of the century,Lloyd's echinacea preparations becamethe best-selling American medicinal plantpreparation sold to physicians in the

  • ALTERNATIVE & COMPLEMENTARY THERAPIESJUNE/JULY 1995 255

    Echinacea is contraindicated inautoimmune diseases.

    United States.7 By 1895, echinacea wasalso used by homeopathic physicians inGermany. Over the next thirty yearsdemand increased, while shortages wereprevalent in Europe. Consequently, in thelate 1930s, commercial cultivation of .purpurea began in Germany, introducingechinacea products to a wide Europeanaudience for the first time.8

    Chemical CompositionNumerous chemical compounds have

    been identified from echinacea species.However, according to researchers R.Bauer and H. Wagner, it is not possible toattribute the effects of echinacea prepara-tions to a specific compound. The mostimportant constituents to which activitycan be attributed include the volatile oil,caffeic acid derivatives, polysaccharides,polyines, polyenes, and isobutylamides(responsible for the "tingling" or "numb-ing" sensation produced on the tongue,especially by E. angustifolia root which hashigher concentrations of this chemicalgroup). Bauer, Wagner, and coworkershave shown that these compounds occurin varying concentrations, depending onthe species, plant part, and other fac-tors.8-9A number of products on the market

    are "standardized" to contain specifiedpercentages of the caffeic acid glycoside,echinacoside. Echinacoside was onceregarded as a significant active ingredient(based on one report of weak antibacterialactivity in the early 1960s). It is notbelieved to be involved in producing theplant group's well-known immunostimu-

    latory effect. It has been shown to be inac-tive in pharmacologie models. Echinaco-side is now considered a component ofminor significance.8,9

    Immunostimulatory ComponentsImmunostimulatory principles have

    been demonstrated, both in fat-soluble

    The Three Species ofEchinacea Used in Medicine

    Echinacea is a genus of the aster family(Asteraceae or Compositae), represented bynine species found exclusively in NorthAmerica. Commonly known as purple cone-flowers (as well as echinacea), three speciesenter international trade as medicinal plants:Echinacea angustifolia (narrow-leaved purpleconeflower), pallida (pale purple coneflow-er), and purpurea (common purple cone-flower). Two species. tennesseens'is and laevigata, are federally listed endangeredspecies. The remaining five species have rela-tively narrow ranges in various parts of theMidwest

    Echinaceaangustifolia_Echinacea angustifolia is a prairie species

    found on barrens and dry western prairiesfrom Minnesota to Texas; west to easternColorado and Montana; and north toextreme southern Saskatchewan and Manito-ba.15 It differs in appearance from otherechinacea species in having a smaller habit(only 20 inches tall), with ray flowers equalto the diameter of the cone (usually one inchor less). Most of the supply is wild-harvested;however, commercial cultivation has begun

    Indications for Echinacea Colds or influenza, especially at onset or

    early stages of symptoms Candidiasis Strep throat Staph infections Urinary tract infections Pelvic inflammatory diseases Tonsil and throat infections Infected hard-to-heal wounds (topical and

    internal) Herpes (topical and internal) Bronchitis

    (lipophilic fractions in alcohol, ether,chloroform, etc.) and water-soluble(hydrophilic) fractions of various speciesand plant parts. Active components oflipophilic (chloroform) extracts mayinclude polyacetylenes, alkylamides, andessential oil components. Enriched alkyl-amide fractions of . purpurea, E. angusti-folia, and E. pallida root ethanol extracts

    with significant cultivated supplies expectedin the next two to three years. Echinoceopallida_

    Echinacea pallida has a more eastern distri-bution, grows to 40 inches in height, and haslong ray flowers (to 4 inches long). It occursin open woods, glades, and rocky prairiesfrom northeast Texas, eastern Oklahoma,and Kansas; north to Iowa and Wisconsin;and east to Indiana. Sparse populations tothe east are considered introduced.15 Mostof the supply is wild-harvested, though culti-vation has been initiated.

    Echinacea purpureaEchinacea purpurea is the most often seen

    species, by virtue of its widespread use as anornamental garden perennial. Unlike otherechinaceas, it has a fibrous root, rather thana taproot, and has toothed, oval leaves(lance-shaped in other common echinaceas).It grows in open woods, prairies, and thick-ets from Louisiana, the northeastern tip ofTexas, north through Ohio and Michigan,and south to Georgia. Known in horticulturesince the 1700s, it has broad natural distribu-tion, but is not sufficiently abundant in thewild for commercial harvest. The entireworld's supply is cultivated.15

  • 256 ALTERNATIVE & COMPLEMENTARY THERAPIESJUNE/JULY 1995

    What Is the "Best"Echinacea?

    Many American herbalists cite Echinaceaangustifolia as the most often used species,primarily as the result of historical prefer-ence. What Is clear, as the result of chemi-cal work by R. Bauer and colleagues inGermany that provides clear distinctionsbetween angustifolio and pallida, is thatmuch of the research published prior to1988 on Echinacea angustifolia was actuallyperformed on pallida. In addition, themajority of the more than 200 pharmaco-logie and clinical studies conducted since1939 have involved purpurea prepara-tions made from the fresh, expressed juiceof the flowering plant. Formulation of purpurea succus (the expressed juice of thefresh flowering plant preserved withethanol) include oral dosage forms, topicalproducts, and injectable forms (availableonly in Germany). Some have stated thatthe numbing sensation produced on thetongue by the sobutylamides of angustifo-lia is an indicator of the quality and identity.This is a common misconception and is notindicative of quality.

    Recommended ReadingEchinaceaNature's Immune Enhancer

    By Steven FosterRochester. VT: Healing Arts Press. 1991

    Echinacea77e Immune HerbBy Christopher HobbsSanta Cruz, CA: Botnica Press. 1994

    EcfiinoceoHandbuch fur Arzie, Apotekerund andere Naturwissenschaftler

    By Rudolf Bauer and Hildebert WagnerStuttgart: Wissenschaftliche Verlagasge-sellschaft GmbH, 1990

    Results of five randomized studies on themmunomodulatory activity of preparationsof echinacea.

    Melchart, D.. Unde, K.. Worku, F.,Sarkady, L. Holzmann, M., Jurcic, K.,Wagner, H.; Alt and Comp Med I (2): 145-160. 1995.

    Recent clinical studies have focused on theoptimum timing and dose of echinacea preparationsin the treatment or prevention of cold and flusymptoms.

    eliminate carbon particles (carbon-clear-ance test) by a factor of 1.5 to 1.7. Cichoricacid from the water-soluble fraction of E.purpurea increased carbon elimination bya factor of 2.1. In the granulocyte smeartest all alcohol (ethanolic) root extracts ofthe three species increased in vitro phago-cytosis by 20 to 30 percent (E. purpureawas most active). Lipophilic (chloroform)fractions of E. angustifolia and E. pallidawere more active than water-soluble frac-tions of those two species, while water-soluble fractions of E. purpurea stimulatedphagocytosis by 40 percent.8-9In the last ten years, much of the pub-

    lished echinacea research has come fromthe research group of H. Wagner and col-leagues, at the Institute for Pharmaceuti-

    ConservationSome botanists, including the most

    recent monographer of the genus, Dr.Ronald McGregor at the University ofKansas, have observed and expressed con-cerns over dramatic declines in wild angustifolia populations (as well as otherspecies) because of current internationaldemand. Large-scale cultivation of angustifolia is currently under way. whichwill increase its desirability in the future.15On the other hand, the entire world'ssupply of purpurea is cultivated, so sup-ply and conservation issues are not aproblem. purpurea preparations havebeen the subject of most recent echinaceascientific studies. It has been used mostextensively by practitioners and comesout slightly ahead of other species in phar-macologie models evaluating capacity tostimulate phagocytosis.

    cal Biology, University of Munich. In par-ticular, research by R. Bauer (now atHeinrich Heine University, Dsseldorf)has provided a much better understand-ing of the identity of echinacea species incommercial products, as well as chemicalcomponents and pharmacologie activityof different species, plant parts, andextraction methods. According to Bauerand Wagner, based on our present knowl-edge, the immunostimulatory activity ofalcoholic and water-soluble extractsdepends on the combined action of sever-al constituents. Alkylamides and thepolar caffeic acid derivative, cichoric acid,contribute to activity of alcoholic extracts.Polysaccharides and cichoric acid areactive constituents in the expressed juiceof E. purpurea, as well as in orally admin-istered powdered whole herb.8'9

    Dose and FormulationsIn Europe, clinicians use echinacea

    preparations as preventives and treat-ments for colds and flu. Recent clinicalstudies have focused on the optimumtiming and dose of echinacea prepara-tions in the treatment or prevention ofcold and flu symptoms. A recent double-blind placebo-controlled trial with 180volunteers studied the effect of an E. pur-purea root ethanol extract (1:5 in 55 per-cent ethanol) in relieving, and reducingthe duration of, flulike symptoms. Com-pared with the placebo control group,volunteers who received a 900-mg dose ofechinacea (equivalent to about 4 droppersfull) had statistically significant improve-ment in symptoms. Those who weregiven half that dose (450 mg) showed nosignificant improvement when compared

  • ALTERNATIVE & COMPLEMENTARY THERAPIESJUNE/JULY 1995 257

    More than 280 echinacea products arenow available in Europe.

    with placebo. The study highlightsthe importance of dose in expectedeffectiveness of echinacea prepara-tions for the treatment of cold and flusymptoms.3,10'11A variety of echinacea formulations

    are available in the United States. Allthree species noted above can beobtained. Echinacea can be taken inmany forms: tinctures, succus, tablets,capsules of both dried root material andtops, fresh tops, and extracts "standard-ized" to echinacoside content or othercomponents. The Germany CommissionE monograph on E. purpurea herb sug-gests a daily dosage of 6 to 9 ml of thepressed juice of the fresh floweringplant, or equivalent preparations.4 TheE. pallida monograph suggests a dailydose equivalent to 900 mg of the herb, astincture (1:5) with 50 percent (V/V)ethanol from natural dry extract (50 per-cent ethanol 7-11:1).12

    International Acceptanceof Clinical Use

    According to Bauer and Wagner, morethan 280 echinacea products are nowavailable in Europe (including homeo-pathic preparations.9 The Europeanliterature provides the majority of cur-rent scientific studies, and the greatestclinical experience with echinaceapreparations.There are...