Echinacea (Immulant)

Uses and Administration

Echinacea, the dried, whole, or cut underground parts ofEchinacea angustifolia (Brauneria angustifolia),E. pallida(B. pallida), orE. purpurea, or the aerial parts of E. purpurea, is reported to have immunostimulant properties. It is used in herbal preparations for the prophylaxis of bacterial and viral infections.

Homoeopathy

Echinacea has been used in homoeopathic medicines under the following names: Echinacea purp ; Echinacea purpurea ; Echinacea purpurea ex planta tota ; Echinacea purpurea, Planta tota ; Echinacea angustifolia ; Echin. an.

(last reviewed 2010-09-02; last modified 2010-05-11)

General references.

(last reviewed 2010-09-02; last modified 2010-05-11)

References

1. WHO. Radix Echinaceae.WHO Monographs on Selected Medicinal Plants, volume 1. Geneva: WHO, 1999. Also available at: Link (accessed 04/02/10)

2. WHO. Herba Echinaceae Purpurae.WHO Monographs on Selected Medicinal Plants, volume 1. Geneva: WHO, 1999. Also available at: Link (accessed 04/02/10)

Respiratory disorders

Echinacea is widely used in herbal preparations to treat upper respiratory-tract infections such as the common cold. Studies1-4 have produced conflicting results, but systematic reviews suggest that most have methodological flaws5 rendering evidence of efficacy unconvincing.5,6A meta-analysis7 of 14 randomised controlled studies suggested that echinacea does have a benefit in decreasing the incidence and duration of the common cold, although it was acknowledged that larger prospective studies controlling for several variables (e.g. species) are needed before it can be routinely recommended. Comparative evaluation of specific preparations is also difficult because of varying composition. Evaluation of the effect of 3 extracts ofEchinacea angustifolia root, each produced by a different extraction method and with defined phytochemical profiles, showed no clinically significant effects by any of them on experimental rhinovirus infection or ensuing illness compared with placebo.8 Alkamides, polysaccharides, and caffeic acid derivatives, which have been proposed as the active components of echinacea preparations, were present in varying amounts in the extracts.

(last reviewed 2010-09-02; last modified 2014-01-15)

References

1. Turner RB, et al.. Ineffectiveness of echinacea for prevention of experimental rhinovirus colds.Antimicrob Agents Chemother. 2000; 44: 1708–9. PubMed

2. Barrett BP, et al.. Treatment of the common cold with unrefined echinacea: a randomized, double-blind, placebo-controlled trial.Ann Intern Med. 2002; 137: 939–46. PubMed

3. Taylor JA, et al.. Efficacy and safety of echinacea in treating upper respiratory tract infections in children: a randomized controlled trial.JAMA. 2003; 290: 2824–30. PubMed

4. Barrett B, et al.. Echinacea for treating the common cold: a randomized trial.Ann Intern Med. 2010; 153: 769–77. PubMed

5. Caruso TJ, Gwaltney JM. Treatment of the common cold with echinacea.Clin Infect Dis. 2005; 40: 807–10. PubMed

6. Linde K, et al.. Echinacea for preventing and treating the common cold. Available in The Cochrane Database of Systematic Reviews; Issue 1. Chichester: John Wiley; 2006 (accessed 31/07/08). PubMed

7. Shah SA, et al.. Evaluation of echinacea for the prevention and treatment of the common cold: a meta-analysis.Lancet Infect Dis. 2007; 7: 473–80. PubMed

8. Turner RB,et al.. An evaluation of Echinacea angustifolia in experimental rhinovirus infections.N Engl J Med. 2005; 353: 341–8. PubMed

Adverse Effects, Treatment and Precautions

Adverse Effects and Precautions

The most common adverse effects reported on short-term use of echinacea were gastrointestinal and skin-related; these were generally transient and reversible.1 Hypersensitivity reactions including anaphylaxis have been reported.1-4The MHRA in the UK advises5 against the use of oral echinacea in children under 12 years of age, because the benefits are outweighed by the low, but potentially severe, risk of allergic reactions in this age group.

(last reviewed 2010-09-02; last modified 2016-11-03)

References

1. Huntley AL, et al.. The safety of herbal medicinal products derived from Echinacea species.Drug Safety. 2005; 28: 387–400. PubMed

2. Mullins RJ, Heddle R. Adverse reactions associated with echinacea: the Australian experience.Ann Allergy Asthma Immunol. 2002; 88: 42–51. PubMed

3. Health Canada. Natural health products and adverse reactions.Can Adverse React News. 2004; 14 2. online

4. Adverse Drug Reactions Advisory Committee (ADRAC). Adverse reactions to complementary medicines.Aust Adverse Drug React Bull. 2005; 24: 2. online

5. MHRA. Press release: echinacea herbal products should not be used in children under 12 years old. (issued 20th August, 2012). Available at: Link (accessed 07/02/13)

Pharmacokinetics

The pharmacokinetics of alkamides extracted fromEchinacea angustifolia roots have been studied1 in human subjects. Fast absorption of some alkamides was shown after oral use; highly lipophilic alkamides could not be detected in plasma.

(last reviewed 2010-09-02; last modified 2010-05-11)

References

1. Woelkart K, et al.. Bioavailability and pharmacokinetics of alkamides from the roots of Echinacea angustifolia in humans.J Clin Pharmacol. 2005; 45: 683–9. PubMed