Echinacea may reduce the symptoms and duration of colds, flu, chronic infections of the respiratory tract, or infections of the lower urinary tract. Topically, it may speed the healing of chronic or slow-healing wounds. Its nonspecific, immune-stimulant activity is currently under investigation, yet it is believed to particularly activate phagocytosis and stimulate fibroblasts.

The species is named for the sharp, spiny pales of its large conical seed head, which resemble the spines of an angry hedgehog (echinos is Greek for hedgehog). Of nine species, the three noted above are used medicinally.

An archeological dig in the region of the Lakota Sioux unearthed echinacea dating to the 1600s. Native Americans used echinacea for snakebites, oral lesions and pain, sepsis, coughs, sore throat, colic, and stomachaches. It was also historically used for scarlet fever, syphilis, malaria, blood poisoning, and diphtheria. Through the 1800s, it was the most widely used plant drug in the United States, dispensed by both eclectic physicians and more traditional doctors. It remained on the national list of official plant drugs in the United States until the 1940s, most likely taken off this list because the conditions it had been used for were then being treated with antibiotics.

Native to North America, echinacea consists of erect stems and alternate or opposite leaves that vary from appearing oval shaped, to oval-shaped ending in points, with varying degrees of teeth along the edges. Flowers grow singly on stem ends. Blooms are large, bear both ray and disk flowers, and have a characteristic cone-shaped receptacle. Roots grow either vertically or horizontally.

E. angustifolia has purplish-red ray flower with darker disk flowers; E. purpurea bears deep rose-purple ray flowers, and pales in the seed head may be tipped with orange. E. pallida's flowers are pale rose, usually drooping.

• Flower
• Seeds
• Leaves
• Roots
• Stems

Polysaccharides, flavonoids, caffeic acid derivatives (echinoside, cichoric acid, chlorogenic acid, and isochlorogenic acids), essential oils, polyacetylenes, alkylamides, alkaloids

Many dozens of preparations are available as urological, wound, and flu remedies, but preparations standardized to 1:2 tincture, with 50% alcohol, 3 to 5 ml qid, made from fresh root or fresh root and cone are preferred. Extracts, tinctures, tablets, capsules, ointments, and stabilized fresh extracts are available. In Europe, intraperitoneal and intravenous forms are sometimes used.

Traditional herbal actions: antimicrobial, immunostimulant, anti-infective, anti-inflammatory, alterative

Clinical applications: Furunculosis and boils, septicemia, nasopharyngeal inflammation, pyorrhea, tonsillitis, carbuncles, abscesses, viral, fungal, and bacterial illness, chronic respiratory infection, colds and flu. Used topically for wounds and dermal ulceration.

Echinacea is an immune stimulant with anti-inflammatory, antiviral, and antibacterial effects. These effects are largely due to nonspecific immune system activation. Carbon clearance tests have measured significant echinacea-induced macrophage activation. Echinacea's polysaccharides are immunostimulatory; its polyacetylenes are anti-inflammatory.

Echinacea increases phagocytosis; activates T lymphocytes; stimulates tumor necrosis factor, properdin, and interferon; inhibits hyaluronidase; and stimulates the adrenal cortex.

One in vitro study showed that when mouse cells were injected with echinacea extracts and incubated, a 24-hour period of resistance to influenza, herpes, and vesicular viruses resulted, likely due to nonspecific T-cell activation.

In animal studies, echinacea's polysaccharides induce tissue regeneration; polyacetylenes are anti-inflammatory when injected. Echinacea also exerts spasmolytic effects to acetylcholine-induced spasm.

A lipid-soluble alkene, Z-1,8-pentadecadiene exerts significant anticancer effects in vivo against Walker tumors in rats and P388 leukemia in mice.

In studies in humans, a respected double-blind trial using 100 patients and an initial 2-day dose of 30 ml of echinacea followed by 15 ml for 4 more days demonstrated that echinacea could reduce the duration of a cold from 10 days to 7. In a double-blind, placebo-controlled study of 180 patients, 450 mg doses of E. purpurea herb extract was as effective as placebo in providing flu relief, but patients receiving 900 mg doses reported significant relief. Prophylaxis was demonstrated in a double-blind, placebo-controlled study: of 108 cold-prone patients, those receiving 4 ml of a proprietary echinacea formula bid significantly reduced cold recurrence. Fifteen drops of E. purpurea tid reduced rheumatoid inflammation up to 21.8% in an uncontrolled study; effects were almost half those exerted by cortisone and prednisone and did not cause additional adverse effects.

As part of a proprietary microbicide, E. purpurea demonstrated possible applications against both acyclovir-resistant and acyclovir-susceptible herpes simplex virus. In a recent double-blind, placebo-controlled crossover trial, E. angustifolia significantly enhanced natural-killer-cell activity against HIV transfected cells. Echinacea's therapeutic potential in these diseases deserves further study.

For immune stimulation during viral or bacterial infection, choose equivalent form of the following and take three times daily.

• 1 to 2 g dried root, as tea
• 2 to 3 ml of 22% ethanol extract standardized to contain 2.4% beta-1,2-fructofuranosides
• 200 mg of powdered extract containing 6.5:1, or 3.5%, echinacoside
• Fluid extract (1:1): 0.5 ml to 1 ml tid
• Tincture (1:5): 1 to 3 ml tid
• Stabilized fresh extract: 0.75 ml tid

Commission E advises to discontinue use of internal E. purpurea and E. pallida after eight weeks, and parenteral E. purpurea after three weeks.

The American Herbal Products Association safety rating is class 1 (safe with appropriate use).

Echinacea is a member of the Compositae family and as such may rarely cause allergic reaction.

Isobutylamides, found only in E. angustifolia roots and E. purpurea seed heads, are responsible for the characteristic numbing and burning sensations when echinacea herb and root extracts are placed on the tongue. Sensation dissipates quickly.

Rare reports of dermatitis. Not recommended for use in systemic diseases (tuberculosis, leukoses, diabetes, collagenosis, multiple sclerosis, AIDS, HIV infection, other autoimmune diseases) or during immunosuppressant therapy. Safety during pregancy has not been studied.

In a study with five outpatients undergoing treatment for inoperable hepatocellular carcinomas, administration of echinacea extract (60 mg/m² IM) with a regimen of low-dose cyclophosphamide and thymostimulin resulted in an increase in the number and activity of natural killer cells (Lersch et al. 1990). In another study involving 15 outpatients with advanced metastatic colorectal cancer, treatment with echinacea extract in addition to cyclophosphamide and thymostimulin decreased tumor markers CA 19-9 and CA 15-3 (Lersch et al. 1992). Echinacea may be a useful adjunct to help re-establish the immune response and counter the immunosuppressive effects associated with chemotherapy.

The recurrence rate of vaginal Candida infections treated with econazole nitrate cream for 6 days was greatly reduced when E. purpurea plant juice was taken concurrently and for an additional 9 weeks, whether intravenously, subcutaneously, intramuscularly, or orally (Coeugniet and Kuhnast 1986). This effect was attributed to echinacea's ability to stimulate the immune system.

Dietary supplement in the United States. E. pallida root approved by Germany's Commission E for relief during flu-like infections; E. purpurea approved topically for chronic ulcers and slow healing wounds, internally for flu-like infections. On the General Sale List in England.

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