Echinacea products available in the United States include tinctures, tablets, capsules, chewable gel tablets, and more. Some are made from echinacea root, while others are derived from the whole plant, including the flowers. Most products are made from E. purpurea or E. angustifolia, or both. Tablets and capsules are both generally made from dried, powdered plant material, sometimes mixed with plant extract. Liquid forms include extracts of fresh or dried plant material preserved in either alcohol or glycerin. Echinacea products often include other herbs, most notably goldenseal (Hydrastis canadensis).
Lack of uniform labeling and the wide variety of available products makes comparisons very difficult. Our sources suggest a daily dosage of 6 to 9 ml (four or five droppersful) of the pressed juice of fresh, flowering plants, or 900 mg of dried, powdered root. Echinacea is likely to lose its effectiveness if taken daily. Begin taking it at the onset of cold or flu symptoms, and continue for no more than two weeks.