Natural Products

Echinacea

Echinacea purpurea, Echinacea augustifolia

Efficacy

• Indications with proven efficacy:
  None
• Indications with possible, but poorly documented efficacy - the use of this product cannot be recommended:
  Poorly healing wounds and ulcers (topically)
  Supportive treatment for chronic respiratory tract infections
  Supportive treatment for lower urinary tract infections Supportive treatment for the common cold
• Also used for these other indications, but with no proof of efficacy:
  Bee stings
  Common cold prevention
  Crohn's disease
  Dizziness
  Dyspepsia
  Eczema
  Gingivitis
  Hemorrhoids
  Migraine
  Recurrent genital herpes
  Rheumatism
  Streptococcus infections
  Syphilis
  Typhoid, malaria, diphtheria

Security

• Risk of Drug Interactions: Low
• Adverse Effects: Not Frequent

What is it?

Echinacea is a perennial plant indigenous to North America. It is widely found growing wild in fields. Today, most of the echinacea used comes from cultivated plants. The applicable parts of echinacea are the aboveground parts (leaves and flowers) which are harvested during the blooming period. Echinacea roots may also be used. There are several species of echinacea, of which the most popular are E. purpurea and E. augustifolia.

Echinacea's chemistry is very complex. Its positive effects are due to all of its active principles, and cannot be attributed to one specific constituent. Polysaccharides, flavonoids, cafeic acid derivatives and essential oils are among its active principles. Echinacea is used orally (capsules, liquid) or topically (liquid).

Warning

In 2004, Canada adopted new regulations that control the manufacturing, packaging, labeling and importing of natural health products. The new regulations also include an adverse reaction reporting system. Products that conform to the regulation's criteria are identified with a natural product number (NPN) or homeopathic medicine number (DIN-HM) and can be legally sold in Canada. This number indicates that the product meets specific criteria for safety and purity, not that it is effective for any indication.

Medicinal plants content varies naturally from plant to plant – just as fruits from the same package may vary in taste and texture. There is no standard to measure the active content of each plant. Thus, efficacy of natural products should be expected to vary from brand to brand as well as from bottle to bottle of the same brand.

For more information about the Natural Health Products Regulations, or to check if a product has been assessed, visit the Health Canada website at http://www.hc-sc.gc.ca/dhp-mps/prodnatur/index-eng.php.

Does it work?

Echinacea stimulates the immune system. Several of its active principles enhance the production and activity of white blood cells (lymphocyte and macrophage). Echinacea also promotes the production of interferons. When applied on the skin, this product promotes healing and reduces local inflammation. It is used in medical conditions, in which it may be of some benefits:

• Poorly healing wounds and ulcers (topically):
  Apply a semi-solid preparation three times a day. It should contain at least 15% expressed echinacea purpura juice.
• Recurrence of vaginal yeast infection (with topical antifungal);
  Supportive treatment for chronic respiratory tract infections;
  Supportive treatment for lower urinary tract infections;
  Supportive treatment for colds:
  A wide variety of doses have been used depending on the formulation (species, parts of plant, extractions). Administer 1000 mg root, 300 mg of aboveground parts or 3 to 4 ml of liquid extract 3 times a day are some examples. Do not continue treatment beyond 8 weeks, since prolonged use may weaken the immune system, possibly because of excess stimulation. An echinacea-free period of 1 to 4 weeks is recommended before another course is initiated.

  Echinacea appears to shorten the duration of a cold if started when symptoms are first notice, but has no preventive effects. Administer 1000 mg 3 times a day. A dose of 1000 mg every two hours for the first day may also be used.

There is insufficient reliable information to conclude that echinacea is effective in any other indication.

Is it safe?

• Echinacea is not associated with any specific toxicity. It may occasionally cause fever, nausea, and vomiting. It may cause an allergic reaction, especially in individuals known to be allergic to ragweed and chrysanthemums.
• It would be prudent to avoid echinacea in people with tuberculosis, collagenosis, multiple sclerosis or autoimmune diseases. In theory, echinacea could interfere with immunosuppressive drugs because its immunostimulating properties.
• It is not recommended to pregnant and lactating women to use echinacea but there is preliminary evidence that echinacea could be used safely during pregnancy.

Clinical notes

• Echinacea is a widely popular natural product. When used according to recommendations, it may be useful to shorten the duration of the common cold. However, it does not appear to prevent its onset. Unfortunately, it is unclear which of the many echinacea preparations should be recommended because of a lack of standardization of echinacea products and a lack of consistency in the study of these products.

References

1. Blumethal M et al. The Complete German Commission E monographs, 1998
2. Natural Medicines Comprehensive Database, Therapeutic Research Faculty, 2007
3. Lininger S. et Al. The Natural Pharmacy, Prima Health, 1998
4. Newall C et al. Herbal Medicine, a guide for health-care professionals, 1996
5. Pierce Andrea, Practical Guide to Natural Medicines, 1999
6. Passeportsanté.net. Échinacée. http://www.passeportsante.net
7. Rotblatt M. et Ziment I. Evidence-Based Herbal Medicine, Hanley & Belfus, 2002
8. Barnes J. et Al. Herbal Medicines, 2e édition, Pharmaceutical Press, 2002
9. Taylor J. CE: Phytomedicinals: Uses, precautions, and drug interactions. Drug Topics 2003;1:79
10. Kligler B. Echinacea. American Family Physician 2003;67:77