Echinacea drug interactions

It is recommended that echinacea not be taken by anyone for more than 8 continuous weeks, and most clinical use is under 2 weeks duration. Echinacea has not yet been shown to be safe in pregnant or breastfeeding women and small children. No specific herb-drug interactions are reported, but for theoretical reasons those taking immunosuppressant drugs should avoid echinacea. 

In view of the multiplicity of CYPs and the many possible botanical-drug interactions, highly efficient clinical study designs using CYP probe cocktails have been explored. Following successful application to St. John s wort, other botanicals that have been evaluated in this fashion include echinacea (42), saw palmetto (43), garlic (39), peppermint oil, and ascorbyl palmitate (44). The results are summarized in Table 1. Curbicin, a botanical... 

Drug Interactions with St. John s Wort and Echinacea... 

Until the role of echinacea in immune modulation is better defined, this agent should be avoided in patients with immune deficiency disorders (eg, AIDS, cancer), autoimmune disorders (eg, multiple sclerosis, rheumatoid arthritis), and patients with tuberculosis. While there are no reported drug interactions for echinacea, some preparations have a high alcohol content and should not be used with medications known to cause a disulfiram-like reaction. In theory, echinacea should also be avoided in persons taking immunosuppressant medications (eg, organ transplant recipients). 

Echinacea. Studies have so far found no drug interactions for this herb. In Germany, echinacea is often combined with antibiotics to treat bacterial infections, although no studies have evaluated the safety or effectiveness of this combination. 

One final consideration of drug interactions involving intestinal CYP3A is the fact that differential modulation of intestinal and hepatic CYP3A is possible. Simultaneous inhibition of intestinal first-pass metabolism and stimulation or induction of hepatic first-pass metabolism has been reported for the interaction between the herbal supplement echinacea (Echinacea purpurea root) and... 

Echinacea remains a popular supplement used as an immunostimulant in the prevention and treatment of infection. Despite inconsistent results from clinical trials attempting to assess effectiveness, its relatively wide margin of safety makes the herb an attractive alternative for prevention and treatment of common infections such as upper respiratory infections. Given the herb s inherent ability to inhibit various C YP450 enzymes, further studies to identify the clinical implications for herb-drug interactions are needed. 

In vitro studies KOI Cynthia Wenner/ Bastyr University Investigate the correlation between formulation composition and bioactivity of echinacea Study herb/drug interactions by examining echinacea s effects on drug-induced inhibition of Cytochrome P450 isoenzymes involved in drug metabolism... 

The National Institutes of Health conducted a double-blind, 3-year study in patients with major depression of moderate severity using St. John s wort and sertraline. This study did not support the use of St. John s wort in the treatment of major depression, but a possible role for St. John s wort in the treatment of miider forms of depression was suggested. Health care providers should alert their patients about potential drug interactions with St. John s Wort. Some other frequently used herbal supplements that have not been evaluated in large-scale clinical trials are ephedra, gingko biloba, echinacea, and ginseng. Any herbal supplement should be taken only after consultation with the physician or other health care provider. 

Gurley, B.J., A. Swain, M.A. Hubbard, et al. 2008. Clinical assessment of CYP2D6-mediated herb-drug interactions in humans Effects of milk thistle, black cohosh, goldenseal, kava kava, St. John s wort, and Echinacea. Mol. Nutr. Food Res. 52(7) 755-763. 

Herb-drug interactions Echinacea purpurea In 15 HIV-infected patients who took antiretroviral drug therapy including darunavir-I-ritonavir for at least 4 weeks. Echinacea purpurea root extract capsules caused no changes in plasma concentrations of darunavir [120. ... 

Moltd J, Valle M, Miranda C, Cedeno S, Negredo E, Barbanoj MJ, Qotet B. Herb-drug interaction between Echinacea purpurea and darunavir-ritonavir in HIV-infected patients. Antimicrob Agents Chemother 2011 55(1) 326-30. 

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