Echinacea

Pronunciation
Scientific names: Echinacea angustifolia DC, Echinacea purpurea (L.) Moench, and Echinacea pallida (Nutt.) Britton. Family: Asteraceae (sunflowers)

Common names: American coneflower, black Sampson, black Susan, comb flower, echinaceawurzel, hedgehog, igelkopfwurzel, Indian head, Kansas snakeroot, narrow-leaved purple coneflower, purple coneflower, purpursonnenhutkraut, racine d'echininacea, rock-up-hat, roter sonnenhut, scurvy root, snakeroot, sonnenhutwurzel

Efficacy rating:

ÒÒÒ...Positive clinical trials

Safety rating:

...Little exposure or very minor concerns.

What is Echinacea?

There are at least 9 species of echinacea. Those most commonly studied are E. purpurea, E. pallida, and E. angustifolia.

Echinacea is native to the United States, specifically Kansas, Nebraska, and Missouri. Because of confusion regarding the identification of echinacea species, much of the early research in Europe attributed to E. angustifolia was probably conducted on E. pallida. E. angustifolia and E. purpurea are perennial herbs with narrow leaves and stout stems that grow from 90 cm to 1.2 m in height that blossom as a single lavender or purple flower head. When chewed, the plant imparts a pungent taste and causes tingling of the lips and tongue.

Slideshow: 18 Herbal Supplements with Risky Drug Interactions

Herbal and Dietary Supplements Deserve Your Attention

What is it used for?

Traditional/Ethnobotanical uses

Echinacea is a popular herbal remedy in the United States. The plant was used in traditional medicine by American Indians and quickly adopted by settlers. During the 1800s, claims for the curative properties of the plant ranged from blood purification to treatment of dizziness and rattlesnake bites. During the early part of the 20th century, extracts of the plant were used to treat infections; however, the use of these products fell out of favor after the discovery of modern antibiotics. The plant and its extracts continue to be used topically for wound healing and internally to stimulate the immune system.

General uses

There is limited evidence that echinacea is effective in shortening the duration of symptoms of upper respiratory tract infections, but it has not shown effectiveness in prevention. Echinacea may have an affect on the immune system. There is also interest in its potential use in cancer therapy, but clinical trials are lacking. The variation in available commercial products and lack of consistency in clinical trials make specific recommendations difficult.

What is the recommended dosage?

Many commercial preparations are available containing components derived from different plant parts as well as from different species and varieties. Recommended doses (all administered 3 times daily) include the following: 300 mg dry powdered extract (standardized to 3.5% echinacoside), 0.25 to 1.25 mL liquid extract (1:1 in 45% alcohol), 1 to 2 mL tincture (1:5 in 45% alcohol), 2 to 3 mL expressed juice of E. purpurea, and 0.5 to 1 g dried root or tea. Echinacea use for more than 8 weeks at a time should be avoided because of the potential for immune suppression. Intravenous use is not recommended.

How safe is it?

Contraindications

Known hypersensitivity to plants of the Asteraceae/Compositae family; any condition in which immune stimulation or suppression would be a disadvantage.

Pregnancy/nursing

Limited clinical evidence, expert opinion, and long-term traditional use suggest that oral echinacea is safe for use during pregnancy at normal dosages. Direct evidence for safety during lactation is lacking. Use with caution.

Interactions

Specific case reports of interactions are lacking.

Side Effects

Adverse reactions are rare. The most commonly reported reactions were allergy, GI upset, and rash. Individuals with allergy to ragweed or related allergens should use echinacea with caution. Potential immune suppression with long-term use has been suggested.

Toxicities

Little is known about the toxicity of echinacea.

References

  1. Echinacea. Review of Natural Products. Facts & Comparisons [database online]. St. Louis, MO: Wolters Kluwer Health Inc; May 2012.

Copyright © 2009 Wolters Kluwer Health

Hide
(web5)