In one the of the largest echinacea clinical trials published to date, scientists have found that a proprietary formula containing 95% echinacea (Echinacea purpurea) herb and 5% root is as effective in addressing early flu symptoms as oseltamivar (Tamiflu®). The results of this randomized, double-blind, controlled trial, which involved 473 people who experienced flu symptoms for 48 hours or less, were published in the open-access journal Current Therapeutic Research in April 2015.
Symptom improvement between the echinacea formula treated group and the oseltamivir group in the first day of the trial was 1.5% compared to 4.1%. Five days later, 50.2% of the echinacea group experienced further relief over 48.8% in the oseltamivir group. Day 10 yielded a recovery rate of 90.1% and 84.8%, respectively. The researchers also noted that there were fewer adverse side effects in the echinacea treatment group, such as nausea and vomiting, symptoms that are commonly associated with oseltamivar.
In conventional medicine, Tamiflu® (which is produced from compounds obtained from star anise, by the way) is currently considered the gold standard in the early treatment of influenza. This medicine, as well as many plant-based formulas like the one used in this trial, work by blocking the neuraminidase enzyme that resides on the surface of influenza virus cells. Because this enzyme would normally penetrate and invade healthy cells in the body, it plays a big role in facilitating viral replication. If the virus succeeds in spreading throughout the body, tell-tale signs of immune system response develop, like fever, chills, nausea and aches and pains.
Previous studies have demonstrated that the anti-viral agents in echinacea are effective against several strains of the influenza virus without promoting resistance. In addition, echinacea extracts have been shown to counter HSN1 influenza viruses that are resistant to Tamiflu®. The trial researchers speculate that the broad spectrum of anti-viral effects of echinacea are due to multiple components acting on cell activity and modulating immune response, including anti-inflammatory effects in virus-infected cells.
This trial finds that the Echinaforce® Hotdrink alcohol-based formula, which also contains elderberry (Sambucus nigra), is as effective as Tamiflu® in treating flu symptoms when taken in the first 48 hours of onset. (Note: Echinaforce® Hotdrink is produced in Switzerland and is not currently available in the U.S.)
Echinacea formulas produce fewer side effects often experienced with Tamiflu®, like nausea and vomiting. Note also that, according to the University of Maryland Medical Center, "The FDA requires Tamiflu to carry a warning that people who have the flu, especially children, may be at increased risk of confusion and injuring themselves after taking Tamiflu."
Echinacea has demonstrated anti-viral activity against multiple strains of influenza but has not shown any potential to create drug-resistant strains.
Echinacea has been shown to work against strains if influenza viruses that have become resistant to Tamiflu.