Echinacea, effects

Delorme, D. and Miller, S.C., Dietary consumption of Echinacea by mice afflicted with autoimmune (type I) diabetes effect of consuming the herb on hemopoietic and immune cell dynamics, Autoimmunity, 38, 453, 2005. 

See, D.M. et al., In vitro effects of echinacea and ginseng on natural killer and antibody-dependent cell cytotoxicity in healthy subjects and chronic fatigue syndrome or acquired immunodeficiency syndrome patients, Immunopharmacology, 35, 229, 1997. 

Morazzoni, P. et al., In vitro and in vivo immune stimulating effects of a new standardized Echinacea angustifolia root extract (Polinacea), Fitoterapia, 76, 401, 2005. 

Cundell, D.R. et al., The effect of aerial parts of Echinacea on the circulating white cell levels and selected immune functions of the aging male Sprague-Dawley rat, Int Immunopharmacol, 3, 1041, 2003. 

Echinacea acts to decrease the effectiveness of certain immunodepressant agents, such as cyclosporine, azathioprine, and tacrolimus. 

Echinacea (Echinacea purpurea) Uses immune system stimulant prevention/Rx of colds, flu as supportive th apy for colds chronic infxns of the resp tract lower urinary tract Action Stimulates phagocytosis cytokine production T resp cellular activity topically exerts anesthetic, antimicrobial, anti-inflammatory effects Efficacy Not established may X severity duration of URI Available forms Caps w/ powdered herb equivalent to 300-500 mg, PO, tid pressed juice 6-9 mL, PO, once/d tine 2-4 mL, PO, tid (1 5 dilution) tea 2 tsp (4 g) of powdered herb in 1 cup of boiling water Noles/SE Fever, taste p -version, urticaria, angioedema Contra w/ autoimmune Dz, collagen Dz, progressive systemic Dz (TB, MS, collagen-vascular disorders), HIV, leukemia, may interfere w/ immunosuppressive therapy Interactions t Risk of disulfiram-like reaction W/ disulfiram, metronidazole T risk of exacerbation of HIV or AIDS W/ chinacea amprenavir, other protease inhibitors X effects OF azathioprine, basiliximab, corticosteroids, cyclosporine, daclizumab, econazole vag cream, muromonab-CD3, mycophenolate, prednisone, tacrolimus EMS Possible immunosuppression... 

There are numerous studies on echinacea in the literature, many of which indicate either an in vitro immune stimulation or a significant clinical reduction in the severity and duration of upper respiratory viral symptoms, especially when taken early in the onset of symptoms. Despite several of these meta-analyses concluding that echinacea is an effective immunomodulator of acute infection, there is still controversy as to the extent of its clinical effectiveness. A number of trials now clearly indicate that echinacea is unlikely to be effective in the prevention of colds, even if it may slightly shorten their course. 

Echinacea appears to be a very safe herb, producing only minor gastrointestinal (GI) side effects and an occasional allergic reaction, usually in atopic patients already sensitized to other members of the Compositae plant family. Anaphylaxis has occurred rarely. Use in HFV is discouraged because of the concern that long-term therapy may eventually suppress the immune system. 

D. Kava is often recommended for anxiety, and it appears significantly more effective than placebo for this condition. Garlic is used for cardiovascular benefits, saw palmetto for prostatic hypertrophy, and ginkgo as a cerebral vasodilator. Echinacea is considered an immunomodulating herb with potential benefit in viral illnesses. 

In general, herbal remedies, including St. John s wort, echinacea, kava kava, and ginkgo, should be avoided. St John s wort is considered an herbal remedy with some serotonergic reuptake inhibition properties and is purported to be helpful with depression. It is sometimes used concurrently with SSRI medications by patients who assume it is relatively free of adverse side effects. 

There are several botanicals that have purported immunostimulating effects. These include Panax ginseng and Echinacea purpurea (74), which have both been used as an immune stimulant. Any potential adverse effect on the pharmacological activity of immunosuppressants has not been reported in patients or evaluated in clinical studies. Given the lack of data, it would be prudent to advise against concurrent intake of these botanicals, and closely monitor changes in efficacy in patients who self-administer these botanicals. 

Gorski JC, Huang SM, Pinto A, et al. The effect of Echinacea Echinacea purpurea root) on cytochrome P450 activity in vivo. Clin Pharmacol Ther 2004 75 89-100. 

All echinacea extracts markedly inhibited CYP-mediated metabolism. The findings with aliquots of the soft gel product extracts were variable (Table 4). Inhibition was moderate to high toward CYP2D6 and 3A4, but only NRP 69 and 72 had an inhibitory effect against CYP2C9. In addition, NRP 71 did not inhibit CYP2C19-mediated metabolism. 

Bauer R. Echinacea drugs-effects and active ingredients. Z Arztl Fortbild (Jena) 1996 90 111-115. 

Table 4 The Effect of echinacea (400 mg q.i.d. x 8 days) on the Disposition of Prototypic CYP Substrates In Vivo...

Bauer R. Echinacea biological effects and active principles. In Lawson LD, Bauer R, eds. Phytomedicines of Europe. Chemistry and Biological Activity. Washington, D.C. American Chemical Society, 1988 140-157. 

The effect of echinacea on the immune system is controversial. In vivo human studies using commercially marketed formulations of E purpurea have shown increased phagocytosis, total circulating white blood cells, monocytes, neutrophils, and natural killer cells but not immunostimulation. In vitro, Epurpurea juice increased production of interleukins-1, -6, and -10, and tumor necrosis factor- by human macrophages. Enhanced natural killer cell activity and antibody-dependent cellular toxicity was also observed with E purpurea extract in cell lines from both healthy and immunocompromised patients. Studies using the isolated purified polysaccharides from Epurpurea have also shown cytokine activation. Polysaccharides by themselves, however, are unlikely to accurately reproduce the activity of the entire extract. 

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