TOC  |  Herbs   

Echinacea (Purple Coneflower, Black Sampson)
Genus Echinacea, 9 species, 3 used medicinally: E. angustifolia, E. pallida, and E. purpurea.

Common trade names:
(Various manufacturers; available in combination) Coneflower Extract, Echinacea, Echinacea Angustifolia Herb, Echinacea Fresh Freeze-Dried, Echinacea Glycerite, Echinacea Herb, Echinacea Herbal Comfort Lozenges, Echinacea Purpurea

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.

Indications: For the treatment of upper respiratory infections, the ‘common cold’ (B)

Traditional Uses:
Traditionally used to treat cough/bronchitis, UTI, as a general immune stimulant, and for external wound healing.

Commercial claims:
Treatment and prevention of common cold, bronchitis, sinusitis, urinary tract infections; antiviral and antibacterial effects; antiseptic; anti-inflammatory; blood purifier. Externally, as wound healer.

Common forms:
Capsules: 125 mg, 355 mg (85 mg herbal extract powder), 500 mg
Tablets: 335 mg
Also available as hydroalcoholic extracts, fresh-pressed juice, glycerite, lozenges, and tinctures.

Dosage:
Expressed juice: 6-9 ml po daily, 2-3 ml TID
Capsule containing the powdered herb: 325-650 mg TID (900mg-1 gm /d)
Tincture (1:5): 3-4 ml (3/4 to 1 teaspoon) TID
Tea: 2 teaspoon (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.
Dried root (or as tea): 1-2

Effects

Physiologic Effects:
Physiologic studies demonstrate increased phagocytic activity and mobility of granulocytes, reproduction of T-helper cells, production of cytokines such as interleukin-1, interleukin-6, and TNF-alpha.4, 5 In-vitro inhibition of influenza, herpes, and vesicular stomatitis virus has been demonstrated.3, 5

Clinical Effects:
Several German studies1, including a meta-analysis2 and review7 indicates that the use of echinacea products at the first sign of URI decreases duration (from 10 days to 7 days) and severity of symptoms.  Several clinical studies do not support prevention of URIs7 .  

Adverse Effects/ Risks:
Allergic reactions in persons allergic to members of the composite family (Asteracea). One report of an anaphylactic reaction. Echinacea does contain a form of pyrrolizidine alkaloids, though there is a structural difference in these alkaloids that, reportedly, render them nontoxic. No reports of hepatotoxicity are recorded, including high dose animal experiments.

Contraindications:
Theoretically may worsen autoimmune diseases by stimulation of immune system, specifically cellular immunity;
may interfere with immunosupressive therapy. Theoretically may worsen HIV disease. German Commission E
warns of possible worsening of diabetic control with parenteral administration. No evidence in pregnancy or lactation.

Drug Interactions:
None known. Theoretic risk of concurrent use decreasing the effect of immunosupressants.

Comments:
There is sufficient pharmacological and clinical data to support the safety and probable effectiveness of various Echinacea preparations in reducing duration and severity of URI symptoms. There is no evidence supporting effective prevention of URIs. When self-treatment with Echinacea fails, patients should be advised not to delay diagnostic evaluation by a physician/health care provider.

There is controversy about which species of Echinacea is best, which plant part is best to use, and which solvent/preparation is best. Most clinical support is for the fresh-pressed juice of aerial parts of E. purpurea, and the roots of E. pupurea/E. pallida. Tinctures may contain significant concentrations of alcohol (15-90%).  Prolonged use of echinacea can theoretically produce immune suppression. Therefore, Echinacea should not be used longer than 8 weeks; 10-14 days should be sufficient for the given indications.

  1. Dorn, M. (1989) Milderung fripper Effekte durch ein pflanzliches Immunstimulans. Natur- und Ganzheitsmedizin, 2:314-319.
  2. Melchart, et al. 1994 Immunomodulation with Echinacea - a systematic review of controlled trials.  Phytomedicine, 1: 245-254.
  3. Fetrow, CW and Avila, JR. Complementary and Alternative Medicines. Springhouse, 1999, p. 232-234.
  4. DerMarderosian, A. Guide to Popular Natural Products, Facts and Comparisons. 1999, p. 69-70.
  5. Newall, C. Herbal Medicines: a guide for health care professionals. London, England. The Pharmaceutical Press, 1996, p. 101-103.
  6. Blumenthal, M, Goldberg A, Brinkmann, J. Herbal Medicine. Expanded Commission E Monographs. IntegrativMedicine, 2000, p. 88-102.
  7. Barrett, et al. Echinacea for upper respiratory tract infection. J Fam Prac, 1999, 48 (8): 628-635.

REF:
Department of Complementary and Alternative Medicine
The Permanente Medical Group
For further information, call 510/987-2028 or 8-427-2028.

         

01102001