Echinacea is a group of North American plants, also called coneflowers, related to sunflowers and daisies. Echinacea products are promoted mainly for the common cold and other respiratory infections, based on the idea that some species may stimulate the immune system.
Also known as: purple coneflower, Echinacea purpurea, Echinacea angustifolia.
Echinacea has no intake value or upper limit, and NCCIH gives no standard amount. Products differ by species (E. purpurea, E. angustifolia, E. pallida) and plant part, and NCCIH notes that soil conditions can affect how active an extract is.
It is sold in the US as a dietary supplement. Under the 1994 dietary supplement law (DSHEA), FDA does not approve dietary supplements before they are marketed, and the maker, not FDA, is responsible for safety and labeling.
What NCCIH says: taking echinacea may slightly reduce your chance of catching a cold, but it is still unclear whether it shortens a cold. One study suggested it might reduce respiratory infections in children, but overall the evidence is not enough to show a clear link. It is unclear whether it helps eczema or other conditions.
Safety, per NCCIH: extracts of E. purpurea, and some mixes with E. angustifolia, are likely safe for most adults for short periods. Some people have allergic reactions, which may be severe; the most common side effects are stomach pain and nausea. Some children in a trial developed rashes, so talk with a child's provider first. Evidence on drug interactions is conflicting, and there are theoretical reasons it might interact with immunosuppressants or caffeine. It is possibly safe for up to 7 days in the first trimester of pregnancy; little is known about breastfeeding.
We could not find a single published half-life or time to peak for echinacea that applies to a supplement dose, so we do not list one. Herbal products are mixtures of many plant compounds, so no single figure would describe them.
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