Echinacea - Guidelines for Using Echinacea - Uses and Benefits

Taxonomic Class

Asteraceae

Common Trade Names

Multi-ingredient preparations: Coneflower Extract, Echinacea, Echinacea Angustifolia Herb, Echinacea Care Liquid, Echinacea Fresh Freeze-Dried, Echinacea Glycerite, Echinacea Herb, Echinacea Herbal Comfort Lozenges, Echinacea Purpurea

Common Forms

Capsules: 125 mg, 355 mg (85 mg herbal extract powder), 470 mg (whole root), 500 mg

Tablets: 335 mg

Also available as candles, glycerite, hydroakoholic extracts, freshpressed juice, lollipops, lozenges, teas, and tinctures.

Source

Echinacea dietary supplements are obtained from the dried rhizomes and roots of Echinacea angustifolia or E. pallida and from the fresh juice of the roots or above-ground parts of E. purpurea.

Chemical Components

Echinacea contains alkylamides, caffeic acid derivatives, polysaccharides, essential oils, and other constituents, including polyacetylene flavonoids and glycoproteins. The plant contains three classes of compounds that exhibit nonspecific immunostimulatory activity: alkylamides, chicoric acids and related glycosides, and high-molecular­weight polysaccharides. The concentration of the pharmacologically active constituents varies, depending on many factors, including the species and plant part used, growing conditions, and extractive process.

Actions

Extract of echinacea stimulates phagocytosis and increases respiratory cellular activity and mobility ofleukocytes. No single component appears to be responsible for the immunostimulating activity, although the caffeic acid derivatives and high-molecular-weight polysaccharides in echinacea stimulate phagocytosis. The alkylamides in the plant are reported to exert local anesthetic and anti-inflammatory effects. Some of these compounds also have insecticidal activity . Caffeoyl conjugates in the plant stimulate the production of properdin and interferon and activate adrenal cortex activity. In vitro studies using the fresh-pressed juice of the aerial portion of E. purpurea and the aqueous extract of the roots inhibited herpes infections, influenza, and vesicular stomatitis virus.

The extract of echinacea can reduce the growth of Trichomonas vaginalis and reduces recurrence of Candida albicans infections . Intraperitoneal administration of purified arabinogalactan in rats caused activation of macrophages against Leishmania enrietti. Arabinogalactan stimulated macrophages to produce tumor necrosis factor, interleukin-1, and interferon beta-2. The lipid-soluble compound 1,8 pentadecadiene exhibits direct anti tumorigenic activity .

The extract has inhibited edema in rats and inflammation in mice. In vitro studies indicate that the polyphenols from echinacea protect collagen against free radical attack.

Reported Uses

Echinacea is claimed to be useful as a wound-healing agent for abscesses, burns, eczema, varicose ulcers of the leg, and other skin wounds and as a nonspecific immunostimulant fur the supportive treatment of upper respiratory tract and urinary tract infections. Two small studies have demonstrated that parenteral administration of purified Echinacin (not available in the United States) may be beneficial as an immunotherapeutic agent in combination with standard chemotherapeutic drugs in the treatment of colorectal and hepatocellular cancers. Several groups of investigators have attempted to define a role for echinacea in the prevention or treatment of colds.

Dosage

Some sources suggest the following doses:

• Capsules containing the powdered herb: equivalent to 900 mg to 1 g P.O. t.i.d.; doses can vary.

• Expressed juice: 6 to 9 ml P.O. daily.

• Tea: 2 tsp (4 g) of coarsely powdered herb simmered in 1 cup of boiling water for 10 minutes. Avoid this method of administration because some active compounds are water-insoluble.

• Tincture: 0.75 to 1.5 ml (15 to 30 gtt) P.O. two to five times daily. The tincture has been given as 60 gtt P.O. t.i.d.

Adverse Reactions

Other: allergic reactions, anaphylaxis .

Interactions

None reported.

Contraindications And Precautions

Echinacea is contraindicated in patients with severe illnesses, including autoimmune diseases, collagen diseases, HIV infection, leukemia, multiple sclerosis, or tuberculosis, and in those who are hypersensitive to plants belonging to the daisy family. Avoid use in pregnant or breast­feeding patients; effects are unknown.

Special Considerations

Alert Many tinctures contain significant concentrations of alcohol (ranging from] 5% to 90%) and may not be suitable for children, alcoholic patients, patients with hepatic disease, or those taking disulfiram or metronidazole .

Alert Echinacea should not be used for longer than 8 weeks; therapy lasting 10 to 14 days is probably sufficient. Urge the patient not to delay treatment for an illness that does not resolve after taking this herb.

Echinacea might adversely influence fertility. In vitro studies have demonstrated echinacea's interference with spermatozoa enzymes . This finding remains to be proven.

Advise the pregnant or breast-feeding patient to avoid using echinacea.

Commentary

The evidence for echinacea appears to be conflicting. More human clinical trial information is needed before a role for echinacea in the treatment or prophylaxis of disease can be defined. It is unknown which Echinacea species and which dosage forms are most valuable.