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Echinacea (Echinacea purpurea)

Be aware that the U.S. Food and Drug Administration does not strictly regulate herbs and dietary supplements. There is no guarantee of strength, purity or safety of products containing or claiming to contain Echinacea. Decisions to use herbs or supplements should be carefully considered. Individuals using prescription drugs should discuss taking herbs or supplements with a pharmacist or health care professional before starting.


Scientists have studied Echinacea for the following health problems:

Common cold treatment
Although multiple low-quality studies have previously suggested that taking Echinacea orally when cold symptoms first begin may reduce the length and severity of the symptoms, a clinical trial reported in July 2005 did not demonstrate any clinical benefit. The sum of the evidence cannot support Echinacea as a treatment for the common cold.
Common cold prevention
Studies have found that taking Echinacea is not helpful for preventing the common cold. Most experts do not recommend chronic use of Echinacea for preventing the common cold.
Respiratory tract infections
Study results of Echinacea for preventing or treating respiratory tract infections are mixed. Further research is needed before a conclusion can be drawn.
Echinacea has also been studied as a treatment for the toxic effects of cancer X-ray therapy (radiation-induced leukopenia), for skin wound healing and for genital herpes, but there are no clear answers in these areas. Early evidence suggests that when Echinacea is used at the same time as the prescription cream econazole nitrate (Spectazole), vaginal yeast infections (Candida) may occur less frequently.

Unproven Uses    

Echinacea has been suggested for many other uses, based on tradition or on scientific theories. However, these uses have not been thoroughly studied in humans, and there is limited scientific evidence about safety or effectiveness. Some of these suggested uses are for conditions that are potentially very serious and even life-threatening. You should consult a health care professional before taking Echinacea for any unproven use.

Bacterial infections
Bee stings
Migraine headache
Skin ulcers
Urinary disorders
Urinary tract infections
Whooping cough (pertussis)

Potential Dangers    


Side Effects

Pregnancy And Breast-Feeding

Echinacea cannot be recommended during pregnancy or breast-feeding. Many experts believe that oral Echinacea is safe, but currently there is not enough information. Pregnant women should absolutely avoid tinctures because of the high alcohol content (15 percent to 90 percent).


Interactions with drugs, supplements and other herbs have not been thoroughly studied. The interactions listed below have been reported in scientific publications. If you are taking prescription drugs, speak with a health care professional or pharmacist before using herbs or dietary supplements.

Interactions With Drugs

Interactions With Herbs And Dietary Supplements

Very few interactions between Echinacea and herbs and supplements have been reported. Echinacea is sometimes sold in combination with goldenseal (Hydrastis canadensis), and goldenseal may reduce the body's ability to absorb vitamin B. Echinacea may affect the way that certain herbs and supplements are broken down by the liver.


The doses listed below are based on scientific research, publications or traditional use. Because most herbs and supplements have not been thoroughly studied or monitored, safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients even within the same brand. Combination products often contain small amounts of each ingredient, and may not be effective. The appropriate dosing should be discussed with a health care professional before starting therapy; always read the recommendations on a product's label. The dosing for unproven uses should be approached cautiously, because scientific information is limited in these areas.

In general, experts suggest using Echinacea for no longer than eight weeks. There is limited scientific information about use for longer periods of time.

For The Common Cold

Adults (Aged 18 Or Older)

Children (Younger Than 18):  The dosing and safety of Echinacea have not been studied thoroughly in children. Discuss doses with a health care professional before your child starts therapy. Some natural medicine practitioners recommend basing children's doses on weight; take the child's weight in pounds, divide by 150, then multiply that number by the recommended adult dose (that will give the child's dose). However, there is no scientific support or safety data for this formula.

For Other Conditions

Echinacea is also available in preparations for the skin (called topical preparations), but no specific doses have been shown to be safe or effective.


Although Echinacea has been suggested for many conditions, it has been most studied as a treatment for the common cold. Study results of Echinacea for reducing the length and severity of symptoms if taken at the first sign of a cold are mixed. Echinacea has not been proven effective for any other health conditions. It should be avoided by pregnant women and by individuals taking amoxicillin. Remember that tinctures can contain large amounts of alcohol and may cause nausea or vomiting if taken with the drugs disulfiram (Antabuse) or metronidazole (Flagyl). Echinacea should be used in recommended doses for no longer than eight weeks. Consult a health care professional immediately if you experience side effects.

The information in this monograph was prepared by the professional staff at Natural Standard, based on thorough systematic review of scientific evidence. The material was reviewed by the Faculty of the Harvard Medical School with final editing approved by Natural Standard.


  1. Natural Standard: An organization that produces scientifically based reviews of complementary and alternative medicine (CAM) topics
  2. National Center for Complementary and Alternative Medicine (NCCAM): A division of the U.S. Department of Health & Human Services dedicated to research

Selected Scientific Studies: Echinacea

Natural Standard reviewed more than 525 articles to prepare the professional monograph from which this version was created.

Some of the more recent studies are listed below:

  1. Barrett B. Medicinal properties of Echinacea: a critical review. Phytomedicine 2003;Jan, 10(1):66-86.
  2. Barrett BP, Brown RL, Locken K, et al. Treatment of the common cold with unrefined Echinacea: a randomized,double-blind, placebo-controlled trial. Ann Intern Med 2002;Dec 17, 137(12):939-946. Comment in: Ann Intern Med 2002;Dec 17, 137(12):1001-1002. Thorax 2003; Mar, 58(3):230. Summary for patients in: Ann Intern Med 2002;Dec 17, 137(12):118.
  3. Barrett B, Vohmann M, Calabrese C. Echinacea for upper respiratory tract infection. J Fam Pract 1999;48(8):628-635.
  4. Bielory L. Adverse reactions to complementary and alternative medicine: ragweed's cousin, the coneflower (echinacea), is "a problem more than a sneeze". Ann Allergy Asthma Immunol 2002;Jan, 88(1):7-9. Comment in: Ann Allergy Asthma Immunol 2002;Jan, 88(1):42-51.
  5. Brinkeborn RM, Shah DV, Degenring FH. Echinaforce and other Echinacea fresh plant preparations in the treatment of the common cold: a randomized, placebo controlled, double-blind clinical trial. Phytomed 1999;6(1):1-6.
  6. Cohen HA, Varsano I, Kahan E, et al. Effectiveness of an herbal preparation containing echinacea, propolis, and vitamin C in preventing respiratory tract infections in children: a randomized,double-blind, placebo-controlled, multicenter study. Arch Pediatr Adolesc Med 2004;Mar, 158(3):217-221.
  7. Del Mar CB, Glasziou P, BMJ Publishing Group. Upper respiratory tract infection. Am Fam Physician 2002;Dec 1, 66(11):2143-2144.
  8. Dorn M, Knick E, Lewith G. Placebo-controlled, double blind study of Echinaceae pallidae radix in upper respiratory tract infections. Compliment Ther Med 1997;5:40-42.
  9. Gallo M, Sarkar M, Au W, et al. Pregnancy outcome following gestational exposure to Echinacea: a prospective controlled study. Arch Intern Med 2000;160(20):3141-3143.
  10. Giles JT, Palat CT III, Chien SH, et al. Evaluation of Echinacea for treatment of the common cold. Pharmacother 2000;20(6):690-697.
  11. Goel V, Lovlin R, Barton R, et al. Efficacy of a standardized echinacea preparation (Echinilin) for the treatment of the common cold: a randomized, double-blind, placebo-controlled trial. J Clin Pharm Ther 2004;Feb, 29(1):75-83.
  12. Grimm W, Muller HH. A randomized controlled trial of the effect of fluid extract of Echinacea purpurea on the incidence and severity of colds and respiratory infections. Am J Med 1999;106(2):138-143.
  13. Henneicke-von Zepelin H, Hentschel C, et al. Efficacy and safety of a fixed combination phytomedicine in the treatment of the common cold (acute viral respiratory tract infection): results of a randomised, double blind, placebo controlled, multicentre study. Curr Med Res Opin 1999;15(3):214-227.
  14. Hoheisel O, Sandberg M, Bertram S, et al. Echinagard treatment shortens the course of the common cold: a double blind, placebo controlled clinical trial. Eur J Clin Res 1997;9:261-269.
  15. Kemp DE, Franco KN. Possible leukopenia associated with long-term use of echinacea. J Am Board Fam Pract 2002;Sep-Oct, 15(5):417-419.
  16. Kim LS, Waters RF, Burkholder PM. Immunological activity of larch arabinogalactan and Echinacea: a preliminary, randomized, double-blind, placebo-controlled trial. Altern Med Rev 2002;Apr, 7(2):138-149.
  17. Lindenmuth GF, Lindenmuth EB. The efficacy of Echinacea compound herbal tea preparation on the severity and duration of upper respiratory and flu symptoms: a randomized, double-blind placebo-controlled study. J Altern Complement Med 2000; 6(4):327-334.
  18. Melchart D, Clemm C, Weber B, et al. Polysaccharides isolated from Echinacea purpurea herb cell cultures to counteract undesired effects of chemotherapy: a pilot study. Phytother Res 2002;Mar, 16(2):138-142.
  19. Melchart D, Linde K, Fischer P, et al. Echinacea for preventing and treating the common cold. Cochrane Database Syst Rev 2000;(2):CD000530.
  20. Melchart D, Walther E, Linde K, et al. Echinacea root extracts for the prevention of upper respiratory tract infections: a double-blind, placebo-controlled randomized trial. Arch Fam Med 1998;7(6):541-545.
  21. Mullins R. Allergic reactions to Echinacea. J Allergy Clin Immunol 2000;105(1 Part 2):268-269.
  22. Mullins RJ, Heddle R. Adverse reactions associated with Echinacea: the Australian experience. Ann Allergy Asthma Immunol 2002;Jan, 88(1):42-51. Comment in: Ann Allergy Asthma Immunol 2002;Jan, 88(1):7-9.
  23. Paulsen E. Contact sensitization from Compositae-containing herbal remedies and cosmetics. Contact Dermatitis 2002;Oct, 47(4):189-198.
  24. Scaglione F, Lund B. Efficacy in the treatment of the common cold of a preparation containing an echinacea extract. Internat J Immunother 1995;11(4):163-166.
  25. Soon SL, Crawford RI. Recurrent erythema nodosum associated with Echinacea herbal therapy. J Am Acad Dermatol 2001;44(2):298-299.
  26. Spasov AA, Ostrovskij OV, Chernikov MV, Wikman G. Comparative controlled study of Andrographis paniculata fixed combination, Kan Jang and an Echinacea preparation as adjuvant, in the treatment of uncomplicated respiratory disease in children. Phytother Res 2004;Jan, 18(1):47-53.
  27. Sperber SJ, Shah LP, Gilbert RD, et al. Echinacea purpurea for prevention of experimental rhinovirus colds. Clin Infect Dis 2004;May 15, 38(10):1367-1371. Epub 2004;Apr 26.
  28. Turner RB, Bauer R, Woelkart K, et al. An evaluation of Echinacea angustifolia in experimental rhinovirus infections. N Engl J Med 2005;Jul 28, 353(4):341-348.
  29. Vonau B, Chard S, Mandalia S, et al. Does the extract of the plant Echinacea purpurea influence the clinical course of recurrent genital herpes? Int J STD AIDS 2001;12(3):154-158.
  30. Yale SH, Liu K. Echinacea purpurea therapy for the treatment of the common cold: a randomized, double-blind, placebo-controlled clinical trial.

Last updated August 01, 2005