Randomised, Double Blind, Placebo-Controlled Trial ofEchinaceaSupplementation in Air Travellers

Objective. To identify whether a standardisedEchinaceaformulation is effective in the prevention of respiratory and other symptoms associated with long-haul flights.Methods. 175 adults participated in a randomised, double-blind placebo-controlled trial travelling back from Australia to America, Europe, or Africa for a period of 1–5 weeks on commercial flightsviaeconomy class. Participants took Echinacea (root extract, standardised to 4.4 mg alkylamides) or placebo tablets. Participants were surveyed before, immediately after travel, and at 4 weeks after travel regarding upper respiratory symptoms and travel-related quality of life.Results. Respiratory symptoms for both groups increased significantly during travel ( P<0.0005 ). However, the Echinacea group had borderline significantly lower respiratory symptom scores compared to placebo ( P=0.05 ) during travel.Conclusions. Supplementation with standardised Echinacea tablets, if taken before and during travel, may have preventive effects against the development of respiratory symptoms during travel involving long-haul flights.