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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). S