GradedHealth

Echinacea

Last reviewed October 2026 · Based on 12 studies

Bottom line

Echinacea may modestly reduce colds and antibiotic use in children, but adult trials found little or no shorter-cold benefit. Products vary widely, and human safety data are limited.

What it helps with

  • Helps prevent colds and infections — Mixed results, evidence grade C (Limited). Child meta-analysis and child RCT show fewer episodes; adult prevention trials were not significant; inconsistent across populations and preparations.
  • Shortens colds — Mixed results, evidence grade C (Limited). Child meta-analysis shows a small shortening; adult trials show no clear benefit; heterogeneous products and small trials.
  • Cuts antibiotic use in children — Benefit, evidence grade C (Limited). Pooled child RCTs with heterogeneity and varied preparations, plus one company-linked trial; downgraded once for inconsistency and once for indirectness.
  • Causes side effects — Harm, evidence grade C (Limited). Child meta-analysis reports moderately more adverse events, mostly mild; the 2021 child trial reports fewer events than vitamin C.

What it is

Echinacea is a daisy-family plant (Asteraceae) whose roots, leaves and flowers are used in herbal products [1]. Products differ in species, plant part and extract, and this affects results [1].

What the research says

In children, a 2025 meta-analysis of nine RCTs of Echinacea purpurea found slightly shorter upper respiratory infections, fewer episodes (risk ratio 0.81) and far less antibiotic use (risk ratio 0.18) [2]. A 2021 child trial found fewer infections and antibiotic courses than vitamin C [3]. In adults, a Cochrane review of 24 trials found no clear benefit for treating colds, and only one of seven duration trials was significant [1]. A 719-person adult trial found a non-significant benefit of about half a day [4].

Doses used in studies

The adult trial gave the equivalent of 10.2 g of dried root on day one, then 5.1 g a day for four more days [4]. The child trial gave 400 mg of a freshly harvested Echinacea purpurea alcoholic extract three times a day in two-month periods with a one-week break [3]. These are study doses, not recommendations.

Safety and interactions

Common side effects: in the child meta-analysis, adverse events were somewhat more common with echinacea than with control (risk ratio 1.38), though generally mild [2]. In the 2021 child trial, 76 adverse events occurred with echinacea and 105 with vitamin C, and only three were possibly related to echinacea [3]. Allergy: a review of complementary medicines lists Echinacea among products linked to severe allergic reactions, including anaphylaxis [5]. Upper limits and toxic doses: the studies read for this page did not report them, and no data were found. Medicine interactions: no human interaction studies were found. In a lab test on liver cells, Echinaforce did not change CYP3A4 gene activity [6]. People taking blood thinners, antidepressants, diabetes or blood-pressure medicines, or immunosuppressants, should ask a pharmacist first. Pregnancy and breastfeeding: no studies were found; a review of herbal remedies advises caution in pregnancy and in children [7]. Liver or kidney disease and bleeding disorders: no studies were found. Liver injury in humans: no human studies were found.

Caveats and open questions

Results differ between children and adults and between products. Several child trials are small or company-linked, and one adult trial found that belief in echinacea influenced colds as much as the pills did [8]. The registry search found no recruiting echinacea cold trials.

References

  1. Echinacea for preventing and treating the common cold.. Cochrane Database Syst Rev, 2014.
  2. Efficacy and safety of Echinacea purpurea in treating upper respiratory infections and complications of otitis media in children: Systematic review and meta-analysis.. Clin Nutr ESPEN, 2025.
  3. Echinacea reduces antibiotic usage in children through respiratory tract infection prevention: a randomized, blinded, controlled clinical trial.. Eur J Med Res, 2021.
  4. Echinacea for treating the common cold: a randomized trial.. Ann Intern Med, 2010.
  5. Risk of anaphylaxis in complementary and alternative medicine.. Curr Opin Allergy Clin Immunol, 2017.
  6. Safety of Herbal Medicinal Products: Echinacea and Selected Alkylamides Do Not Induce CYP3A4 mRNA Expression.. Evid Based Complement Alternat Med, 2011.
  7. A Critical Approach to Evaluating Clinical Efficacy, Adverse Events and Drug Interactions of Herbal Remedies.. Phytother Res, 2016.
  8. Placebo effects and the common cold: a randomized controlled trial.. Ann Fam Med, 2011.