An Herbal Myth Challenged: Does Echinacea's immune system activity diminish with continuous use?
by Ed Smith

I am on a mission to dispel the modern herbal myth that people should not take the herb Echinacea for long periods of time because its immune-enhancing activity diminishes with repeated and continuous dosing. Unfortunately this misinformation has now become “common knowledge,” although it has never been scientifically or clinically proven. This myth evolved from the “theory” that because Echinacea “stimulates” the immune system its continuous use will cause the immune system to “fatigue” and diminish its activity. Interestingly, the medical and pharmacological researchers of Echinacea do not refer to the herb as an immuno-STIMULANT, but in-stead use the term immuno-MODULATOR, which much better describes Echinacea's pharmacodynamics.

Extensive medical and pharmacological research on Echinacea has revealed multiple immuno-modulating actions (e.g., increases phagocytic action of immune cells, enhances properdin/complement system, enhances production of alpha-1 & -2 gamma globulins, inhibits hyaluronidase enzyme activity and enhances polymerization of hyaluronic acid, enhances wound healing by augmenting growth of healthy new connective tissue, increases killer T-cell production, inhibits tumor growth, is anti-inflammatory, increases interferon levels and is thereby anti-viral, and more). However, all this research has never shown any evidence which indicates that any of these immuno-modulating actions are decreased by continued use of Echinacea.

But let's set science aside for a moment and look at Echinacea's clinical use by the Eclectic physicians who practiced medicine from the mid-1880s until the 1930s. Tens of thousands of Eclectic physicians prescribed hundreds of millions of doses of Echinacea for many decades and yet in their voluminous medical texts and journals they never once mentioned anything about diminished curative success with Echinacea (for any reason). If they did indeed see such, one would assume it would have been mentioned in their literature at least once, if not scores of times. And while their empirical evidence cannot be considered scientific proof, I have much confidence in the bedside experience of these physicians who “saw it all.” I have offered a friendly challenge to several prominent herbalists and herbal authors who claim Echinacea's immuno-activity diminishes with continuous use. I've asked them to supply at least one reference that supports their claim -- either from modern medical research, or from the Eclectic or Physiomedicalist literature, or from traditional folk medicine sources. So far no one has been able to supply even one reference. For me, I have to have something in order to believe -- either modern scientific evidence or historical references, and definitely more than theory and conjecture alone. What I do know for sure is that Echinacea “works” -- and does its immunomodulating job dose, after dose, after dose, after ...