Echinacea is a type of daisy that is often touted as being able to prevent or cure the common cold. It is available in supplement form with a handy warning that it is not intended to cure or prevent any disease. You know, the standard disclaimer that products that haven't been proven to have any medical efficacy are required to have. With the supplement industry eclipsing tens of billions of dollars of revenue every year, one must wonder if this herbal remedy has any medical value at all.
It should be easy to prove if this herbal remedy has any use.
Let's look at what the studies say:
From 1946 to 2013, at least twenty-four double-blind clinical trials totaled 4631 participants with 33 varieties of echinacea preparations. Ok, that sounds pretty thorough.
What were the results?
Unfortunately for the supplement manufacturers, there was no evidence of echinacea being proven to provide medical efficacy in the treatment or prevention of the common cold. The best result was a study reporting "weak benefit of questionable medical significance." See below for some study links.
The most positive results seem to come from the NIH. They rate echinacea, based on data from the Natural Medicines Comprehensive Database, as possibly effective for reducing some cold symptoms. The NIH states that some studies have shown positive results though others have shown no results.
The NIH does state that there is a somewhat proven medical efficacy in reducing the re-occurrence of vaginal yeast infections Â when combined with certain creams. There was no data available when used alone.
There have also been studies on the curative effect of echinacea on other illnesses. However, there have yet to be enough studies conducted for a strong conclusion either way. We haven't found a case where it is particularly useful, but we haven't yet ruled it out.
The following illnesses have been studied with inconclusive results: anxiety, gingivitis, herpes simplex, HPV, influenza, leukopenia, tonsillitis, uveitis, warts, UTIs, migraines, chronic fatigue syndrome, eczema, hayfever, allergies, bee stings, and ADHD.
Alright, we've demonstrated that there are dubious results at best. What are the risks? Well, the reported side effects include fever, nausea, vomiting, stomach pain, diarrhea, sore throat, dry mouth, headache, tongue numbness, dizziness, insomnia, disorientation, and joint/muscle aches. There have also been demonstrated instances of increased risks of complications in individuals suffering from auto-immune disorders. Furthermore, several known complications can occur when prescribed medications are combined with this herb, as echinacea is known to alter liver function.
Ultimately, this is probably something you should steer clear of.
Karsch-Volk M, Barrett B, Kiefer D, Bauer R, Ardjomand-Woelkart K, Linde K (2014). "Echinacea for preventing and treating the common cold." Cochrane Database Syst Rev(Systematic review)
"Echinacea." MedlinePlus, US National Institutes of Health, Bethesda. 2014. Retrieved 15 December 2014
The Flu, the Common Cold, and the Complementary Health Practicesâ€. U.S. Department of Health and Human Services. Retrieved 1 November 2014.
Echinacea is also known by the following names: American Cone Flower, Black Sampson, Black Susans, Brauneria Angustifolia, Brauneria Pallida, Comb Flower, Coneflower, Hedgehog, Indian Head, Kansas Snakeroot, Narrow-Leaved Purple Cone Flower, Pale Coneflower, Purple Cone Flower, Racine d'echininacea, Red Sunflower, Rock-Up-Hat, Roter Sonnenhut, Rudbeckie Pourpre, Scurvy Root, Snakeroot, Sonnenhutwurzel