Echinacea, safety

Huntley AL, Thompson Coon J, Ernst E. The safety of herbal medicinal products derived from Echinacea species a systematic review. Drug Saf. 2005 28 387-400. 

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. 

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. 

Echinacea must first be approved as a GRAS ingredient before it can legally be added to food. In many European countries, health claims are not permitted on food products, while in other countries, such as Japan, claims are allowed under the Foods for Specified Health Use (FOSHU) system. The benefits of Echinacea in laboratory studies show promise and potential that functional foods may come from this research, provided that the studies support the safety of Echinacea. 

Unfortunately, persistent misconceptions about botanical safety become part of the conventional wisdom about herbs, as the original case reports are repeatedly cited without any acknowledgement of the explicatory letters that follow in subsequent volumes of the journals in which the original reports or letters appeared. In addition to this unfortunate situation, adverse effects of particular herbs have been predicted, in the absence of case reports or even in vitro studies, on the basis of the chemical composition of the herb in question. For instance, Miller (1998) warned about the expected hepatotoxicity of Echinacea spp. based on the occurrence of the pyrrolizidine alkaloids tussilagine and isotussilagine. These compounds are indeed present (at 0.006%) in Echinacea root, but they are nontoxic because they lack the structural features (1,2 unsaturation in the pyrrolizidine ring) mentioned above necessary for hepatic activation into reactive pyrroles. 

Some of the most popular nutraceutical products marketed today are botanicals such as St. John s wort, echinacea, ginkgo biloba, saw palmetto, and ginseng. Unfortunately, manufacturers are not required to prove their safety or efficacy before marketing them. Dosages are not standardized. The quality of the raw source and the plant parts used are not regulated. And, unlike prescription drugs or over-the-counter medicines, there is no federal quality... 

Gallo M, Au W, Koren G. The safety of echinacea use during pregnancy a prospective controlled cohort study. Teratology 1998 57 283. 

The use of botanical or herbal medications has increased markedly in the past decade. Popular botanical products in the USA include echinacea, garlic, ginseng, gingko, Ma-huang, psyllium, St. John s wort, and saw palmetto. These natural medicinals are available without prescription and, unlike over-the-counter medications, are considered to be nutritional supplements rather than drugs. As such, these substances are marketed without FDA review of efficacy or safety and there are no mandated require-... 

Erhst E The risk-benefit profile of commonly used herbal therapies ginkgo, St. John s Wort, ginseng, echinacea, saw palmetto, and kava. Ann Intern Med 2002 136 42-53. [PMID 11777363] (A detailed analysis of the available scientific evidence on six popular herbal products, including information on efficacy, dosage, and safety.)... 

Limited human data has not indicated any safety concerns for use of Echinacea species during pregnancy (Gallo et... 

No information on the safety of Echinacea spp. during lactation was identified. While this review did not identify any concerns for use while nursing, safety has not been conclusively established. 

No information on the safety of Echinacea spp. during lactation was identified. 

Modarai, M., E. Silva, A. Suter, M. Heinrich, and A. Kortenkamp. 2009. Safety of herbal medicinal products Echinacea and selected alkylamides do not induce CYP3A4 mRNA expression. Evid. Based Complement. Altemat. Med. 

Perri, D., J.J. Ehigoua, E. Mills, and G. Keren. 2006. Safety and efficacy of echinacea (Echinacea angustifolia, E. purpurea and E. pallida) during pregnancy and lactation. Can. J. Clin. Pharmacol. 13(3) e262-e267. 

Taylor, J. A., W. Weber, L. Standish, et al 2003. Efficacy and safety of echinacea in treating upper respiratory tract infections in children A randomized controlled trial. /. Am. Med. Assoc. 290(21) 2824-2830. 

Preparations containing extracts of the plant Echinacea (family Compositae) are widely used by patients and practitioners in some European countries for preventing and treating upper respiratory tract infections as well as more generally for stimulating the body s own defense mechanisms. At present, about 1000 preparations are obtainable which contain extracts of Echinacea alone or in combination with other plant extracts [1]. In 1993 German physicians prescribed over 3 million daily doses of the five leading preparations with a cost of 50 million DM [2]. As these preparations are often sold over the counter the actual overall use is probably much more widespread. Despite this frequent use, there is considerable debate about the effectiveness of Echinacea extracts, and doubts have been raised about safety in the (relatively rare) case of parenteral application [3,4]. 

The safety of Echinacea preparations has repeatedly stimulated polemic public discussions. Large-scale drug-monitoring studies which would allow a reliable estimate of the occurrence and frequency of side-effects do not exist. Cases of severe anaphylactic reactions, mainly after parenteral application, have been reported [1, 3] however, in some of the cases a causality seems highly questionable. Nevertheless, there can be little doubt that the parenteral application of Echinacea extracts or combinations containing Echinacea bears some risk in susceptible individuals. Therefore, the majority of the manufacturers in Germany have withdrawn the... 

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