Echinacea

Use by Plains peoples as recorded by ethnobotanists

A plant guide issued by the US Department of Agriculture, drawing on the ethnobotanist Kelly Kindscher's 1992 work, describes narrow-leaved purple coneflower (Echinacea angustifolia) as having been, and still being, the most widely used medicinal plant of the Plains Indians. The guide lists recorded uses by named nations, among them chewing the root for coughs and sore throats (Kiowa), root poultices for enlarged glands (Pawnee, Ponca, Dakota and Winnebago) and use for toothache and snake bite across several nations.

These are second-hand ethnobotanical summaries compiled by outside authors, not statements made by the communities themselves. Uses differ by nation and by plant part, and the guide does not describe ceremonial or restricted knowledge. The sources reviewed do not show how any of these uses relate to the products sold today.

Adoption in Eclectic medicine and in Europe

A 2024 review of echinacea extracts states that the plant was employed in Eclectic medicine, a nineteenth-century American botanical medical movement, to treat septic conditions, and that it was regarded as an anti-infective agent. The review gives no dates or practitioner names for this adoption, and the sources reviewed for this page do not document its early history in detail.

Reviews also describe echinacea as widely used in some European countries and in North America for upper respiratory infections, and one review notes that in Europe the plant is cultivated for medicinal use mainly in Germany. The sources reviewed do not trace the steps by which German phytotherapy took up the plant.

Plant names and common names

Echinacea is a genus of perennial plants in the daisy family, Asteraceae, native to the eastern and central United States and now widely cultivated. The National Center for Complementary and Integrative Health names three species in common use, E. purpurea, E. angustifolia and E. pallida, and lists purple coneflower and American coneflower as common names. The USDA plant guide records further older names for E. angustifolia, including Kansas snakeroot.

One name, many products

The Cochrane review stresses that products sold as echinacea differ appreciably in composition, because of different species, plant parts, extraction methods and added components. A 2024 review likewise notes that composition varies between species and between roots, stems, leaves and flowers. The word echinacea on a label therefore does not identify a single material, and findings for one preparation cannot be assumed to apply to another.

Forms of preparation

The Cochrane review lists the main forms as pressed juices stabilized with alcohol, alcohol tinctures and tablets made from dried extracts, prepared from the root, the aerial herb, the flower or the whole plant. The National Center for Complementary and Integrative Health states that echinacea products are mainly sold as dietary supplements, and that some topical products are marketed for skin problems. Related Machipedia pages on how such products are categorized include Dietary Supplements and Plant Medicine.

How it is used and by whom

Consumers take echinacea products by choice, and the reviews describe use both when a cold begins and as a preventive course taken over weeks. Herbalists and naturopathic practitioners may recommend it, and it sits within the wider field described on the Herbal Medicine page, alongside Naturopathy. This page does not give doses or product advice.

Colds and respiratory infections

The National Center for Complementary and Integrative Health states that echinacea is sold mainly for colds and other respiratory infections, on the idea that it stimulates the immune system. A 2024 review of preclinical work reports laboratory findings on immune cells and on some viruses and bacteria, and also states that variability in plant chemistry is a challenge. Laboratory findings are not evidence of effects in people.

Other uses

The same federal source states that much less research exists for uses beyond colds and respiratory infections, and that usefulness for conditions such as eczema is unclear. Echinacea is sometimes also discussed alongside related herbs such as Elderberry for seasonal respiratory complaints, but the sources reviewed here do not compare the two.

Cochrane review of colds

The 2014 Cochrane review (Karsch-Völk and colleagues) included 24 double-blind placebo-controlled trials with 4,631 participants of echinacea mono-preparations. Because products and trials differed so much, the main analysis was not pooled. None of 12 prevention comparisons reporting people with at least one cold found a significant difference, though a post hoc pooling suggested a 10 to 20 percent relative risk reduction. Of seven treatment trials reporting duration, only one showed a significant effect.

The authors concluded that echinacea products had not been shown to benefit colds already begun, that a weak benefit from some products was possible, and that prevention trials showed positive but non-significant trends of questionable clinical relevance.

Trials funded by the National Institutes of Health

In a 2005 trial (Turner and colleagues), 437 volunteers received one of three chemically defined Echinacea angustifolia root extracts or placebo around experimental rhinovirus type 39 infection. Results for 399 volunteers showed no statistically significant effect on infection rates or symptom severity.

In a 2010 Wisconsin trial (Barrett and colleagues), 719 people with new colds received no pills, placebo, blinded echinacea root or open-label echinacea. The blinded comparison showed nonsignificant trends in severity (P = 0.089) and a 0.53-day difference in duration. The authors reported that higher-than-expected variability limited power to detect small benefits.

Later meta-analyses and trials

A 2015 meta-analysis of six selected placebo-controlled studies (Schapowal and colleagues) reported reduced risk of recurrent respiratory infections, and a 2024 meta-analysis of 30 trials (Gancitano and colleagues) reported fewer infections, complications and antibiotic use, with differences between preparations. A 2019 review (David and Cunningham) found a risk ratio of 0.78 for prevention, no evidence of an effect on duration, and limits from selective reporting and heterogeneity. A 2012 trial of one fresh-plant extract over four months (Jawad and colleagues) reported fewer cold episodes than placebo.

Children and overall picture

A 2017 review of herbal medicines in children found four echinacea trials and could draw no firm conclusion, and a 2025 meta-analysis of nine trials in children reported moderately more adverse events and bias from heterogeneity. The National Center for Complementary and Integrative Health states that echinacea may slightly lower the chance of catching a cold, that it is unclear whether it shortens one, and that evidence for children is not strong enough to confirm a benefit.

Retail species labeling

In a 2003 study published in the Archives of Internal Medicine (Gilroy and colleagues), 59 single-herb echinacea preparations bought in the Denver area in August 2000 were analyzed by thin-layer chromatography. Six (10 percent) contained no measurable echinacea, and the assayed species matched the label in 31 (52 percent). Of 21 products labeled standardized, 9 (43 percent) met the quality standard on the label. The authors concluded that retail echinacea often does not contain the labeled species and that a standardization claim did not indicate accurate labeling.

Limits of that finding

The Denver sample is a single region and year, and products have changed since 2000, so the sources reviewed do not show current market quality. The Cochrane review and a 2024 review both describe variability in plant chemistry as a barrier to interpreting trials, which is the reason reviewers give for caution about comparing results across products.

Reported adverse effects

A 2005 systematic review of echinacea safety (Huntley and colleagues) drew on clinical studies and spontaneous reporting programmes and concluded that adverse events are not commonly reported, with gastrointestinal upsets and rashes the most frequent. The National Center for Complementary and Integrative Health likewise lists digestive effects such as abdominal pain and nausea as most common and states that allergic reactions can occur and may be severe. Short-term use of E. purpurea extracts is described as likely safe for most adults, and these statements apply to the products and durations studied.

Allergy and daisy-family plants

Echinacea belongs to the daisy family, which also includes ragweed and chrysanthemum. Huntley and colleagues reported that echinacea can be associated with rare but sometimes severe allergic reactions and advised that people with allergy or asthma carefully consider its use. The Cochrane review similarly regards allergic reactions as the most relevant potential adverse effect, and cites a trial in children in which rash increased by an absolute 5 percent.

Interactions, pregnancy and who should ask a clinician

The federal summary states that evidence is conflicting on whether echinacea interacts with drugs processed by the liver, and that interactions with immunosuppressant medicines have been suggested in theory. A 2018 review of echinacea notes a case-based concern in which immunostimulatory supplements were linked to activation of autoimmunity, and older monographs and some reviews advise caution in people with autoimmune disease, although the sources reviewed do not establish how often this occurs. Huntley and colleagues judged use in pregnancy and lactation ill-advised because of limited data.

People who are pregnant or breastfeeding, who have allergies or asthma, who take prescription medicines or have a weakened immune system or autoimmune disease, and parents considering it for a child, are advised by these sources to ask a health care provider first. Echinacea should not delay or replace care for symptoms that are severe, persistent or worsening, or for infections that need medical assessment. The Cochrane authors advise against injected use because safety and effectiveness are not established.