| Effect | Increase |
| Values | Mean and SEM. 10⁹ /L. Placebo: before 5.8 ± 0.2, 2 days 6.1 ± 0.3, 7 days 5.7 ± 0.2. Echinacea: before 5.7 ± 0.2, 2 days 6.7 ± 0.4, 7 days 6.6 ± 0.5 |
| Trial Design | Randomized trial |
| Trial Length | 1-7 Days |
| Number of Subjects | 62 |
| Sex | Both Genders |
| Age Range | 18-29, 30-44, 45-64, 65+ |
In a randomized, double-blind, placebo-controlled trial, 150 participants who were prone to colds were recruited, and 62 developed a cold and were given 8 doses of 5 ml of a 40% ethanol echinacea extract containing alkamides/cichoric acid/polysaccharides at concentrations of 0.25/2.5/25.5 mg/mL, respectively on the first dose and 3 on each of the next 6 days, or placebo.Funding issues for this study:
Total daily symptoms were lower when taking echinacea than placebo, and the difference was statistically significant after the third day. There was also an increase in total leukocytes, monocytes, and neutrophils, but not lymphocytes, and the respiratory burst capacity of neutrophils, while there was a decrease in erythrocyte superoxide dismutase units during echinacea.
Contract/grant sponsor: Factors R & D Technologies, Burnaby, BC,
Canada.
