Evaluation of Echinacea for the prevention and treatment of the common cold: A meta-analysis

University of Connecticut School of Pharmacy, Storrs, CT, USA.
The Lancet Infectious Diseases (Impact Factor: 22.43). 07/2007; 7(7):473-80. DOI: 10.1016/S1473-3099(07)70160-3
Source: PubMed


Echinacea is one of the most commonly used herbal products, but controversy exists about its benefit in the prevention and treatment of the common cold. Thus, we did a meta-analysis evaluating the effect of echinacea on the incidence and duration of the common cold. 14 unique studies were included in the meta-analysis. Incidence of the common cold was reported as an odds ratio (OR) with 95% CI, and duration of the common cold was reported as the weighted mean difference (WMD) with 95% CI. Weighted averages and mean differences were calculated by a random-effects model (DerSimonian-Laird methodology). Heterogeneity was assessed by the Q statistic and review of L'Abbé plots, and publication bias was assessed through the Egger weighted regression statistic and visual inspection of funnel plots. Echinacea decreased the odds of developing the common cold by 58% (OR 0.42; 95% CI 0.25-0.71; Q statistic p<0.001) and the duration of a cold by 1.4 days (WMD -1.44, -2.24 to -0.64; p=0.01). Similarly, significant reductions were maintained in subgroup analyses limited to Echinaguard/Echinacin use, concomitant supplement use, method of cold exposure, Jadad scores less than 3, or use of a fixed-effects model. Published evidence supports echinacea's benefit in decreasing the incidence and duration of the common cold.

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Available from: Craig I Coleman, Mar 06, 2014
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    • "Immunomodulatory, antiinflammatory , antifungal, antiviral, and anticancer effects are attributed to various chemical constituents present in these plants (Barrett 2003; Mistrikova and Vaverkova 2006; Miller 2005). Echinacea has emerged as an important herbal medicine in the treatment of common cold and upper respiratory infections, reducing duration, and/or severity of symptoms (Hudson 2010; Hudson and Vimalanathan 2011; Schoop et al. 2006; Shah et al. 2007). E. purpurea, E. angustifolia, and E. pallida are rich in various phytochemicals including phenolic compounds such as phenylpropanoids or caffeic acid derivatives (CADs), flavonoids, terpenoids, and lipids (polyacetylenes); nitrogenous compounds such as alkylamides (or alkamides), alkaloids, and polysaccharides (Barnes et al. 2005; Mistrikova and Vaverkova 2006). "
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    ABSTRACT: Caffeic acid derivatives (CADs) are a group of bioactive compounds which are produced in Echinacea species especially Echinacea purpurea, Echinacea angustifolia, and Echinacea pallida. Echinacea is a popular herbal medicine used in the treatment of common cold and it is also a prominent dietary supplement used throughout the world. Caffeic acid, chlorogenic acid (5-O-caffeoylquinic acid), caftaric acid (2-O-caffeoyltartaric acid), cichoric acid (2, 3-O-dicaffeoyltartaric acid), cynarin, and echinacoside are some of the important CADs which have varied pharmacological activities. The concentrations of these bioactive compounds are species specific and also they vary considerably with the cultivated Echinacea species due to geographical location, stage of development, time of harvest, and growth conditions. Due to these reasons, plant cell and organ cultures have become attractive alternative for the production of biomass and caffeic acid derivatives. Adventitious and hairy roots have been induced in E. pupurea and E. angustifolia, and suspension cultures have been established from flask to bioreactor scale for the production of biomass and CADs. Tremendous progress has been made in this area; various bioprocess methods and strategies have been developed for constant high-quality productivity of biomass and secondary products. This review is aimed to discuss biotechnological methods and approaches employed for the sustainable production of CADs.
    Full-text · Article · Jul 2014 · Applied Microbiology and Biotechnology
    • "Echinacea is one of the most used medicinal plants in herbal medicines and food supplements. The Native American Populations such as Cheyenne, Choctaw, Comanche, Crow, Dakota, Delaware, Pawnee, Hidatsa, Sioux and others used Echinacea, for the treatment of several diseases such as cold, flu, burns, wounds, snakes bites, general inflammatory condition, etc. (Morazzoni et al., 2005; Barnes et al., 2005; Barrett, 2003; Goel et al., 2004; Shah et al., 2007). Nowadays, Echinacea spp. "

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    • "2007 [46] + + Herbal remedies Ecchinacea, thuja, aronia, aloe, grapefruit concentrates, traditional Tibetan herbs [48] [49] [51] +/À Homeopathy Calcarea carb, Pulsatilla, Sulphur 2005 [53] À Fungal derived remedies Beta-glucan 1999, 2008 [54] [55] À "
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    ABSTRACT: Parents of children suffering from recurrent respiratory infections can be persuaded by advertisements to pressure their family physicians and pediatricians for "immune-stimulating enhancements". However, the evidence base behind these immune stimulants is usually lacking. Often there is no peer-reviewed studies available that support claims made by "immune-booster" supplements. In this review, we critically analyze most of the marketed immuno-active drugs (including vitamin preparations, dietary supplements, homeopathic remedies, Ecchinacea, bacterial lysates, and probiotics) and identify the necessity to exclude an immunodeficiency in every child suffering from recurrent respiratory tract infections.
    Full-text · Article · Oct 2013 · Paediatric Respiratory Reviews
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