Synergy in Herbal Medicines
Eric Yarnell, ND, RH(AHG)


Artemisia annua
Medicinal plants


In the following paper, we will review the available literature on synergy and additive effects involving medicinal herbs and herbal extracts. Several types of synergistic interactions are discussed, including apparently inactive constituents enhancing the effects of apparently active constituents within and between herbal medicines, various herbal compounds altering the absorption of others, reduction in toxicity of some herbal constituents by others, and direct synergistic therapeutic effects when active constituents are combined within and between many medicinal herbs. Species discussed include Artemisia annua (sweet Annie, qīng hāo), Ammi visnaga(khella), Glycyrrhiza glabra (licorice), G. uralensis (Chinese licorice, gān co), Panax ginseng (Asian ginseng, rén shēn), Mahonia aquifolium (Oregon grape), Berberis aetnensis (Mt. Etna barberry), B. trifoliolata (algerita), B. fendleri (Colorado barberry), and Coptis chinensis (goldthread, huáng lián). Part 2 of this article will continue this review on other medicinal herb species.



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