Echinacea myth: Phagocytosis not diminished after ten days
by Paul Bergner
Medical Herbalism 04-30-94 6(1): 1
It has been widely reported in English language herbal circles in recent years that echinacea loses some of its ability to stimulate the immune system after about ten days of treatment. It is thus often recommended that patients take echinacea long-term in a ten-day-on, five-day-off pattern. This recommendation appears to be without scientific basis (although that does not rule out the clinical benefit of periodic breaks in the echinacea dose. A study by Jurcic et al, which was published in 1989 in German, is invariably given as the basis for this recommendation. The accompanying graph, from that article, indeed shows phagocytosis (one measure of immune activity) declining after day five and trailing off to a plateau from day eight to ten. However, the dose of echinacea, indicated by the vertical arrows at the bottom left of the graph, (and reported in the body of the article), was discontinued after day five. The original article is in German, and the duration of the dose was apparently not translated, or was mistranslated. Thus, instead of showing any diminished response to echinacea over ten days, it shows a persistent elevation of immune response for five days even after echinacea is discontinued. The plateau at the end of the curve; from days eight through ten, shows an increase in phagocytosis of 20%. Our thanks to Kerry Bone, PhD, of Australia for bringing this to our attention.
Jurcic K, Melchart D, Holsmann M,
Martin P, et al. “Zwei probandenstudien zur stimulierung der
granulozyphagozytose durch echinacea-extract-haltige präparate.”
Zeitschrift för Phytotherapie 1989;10:67-70