Elderberry Extract Outpatient Influenza Treatment for Emergency Room Patients Ages 5 and Above: a Randomized, Double-Blind, Placebo-Controlled Trial
J Gen Intern Med (2020)
- Randomized clinical trial (RCT). Note: this was not included in the meta-analysis summarized above because it was published later. Comparison of symptom improvement in influenza symptoms in subjects taking elderberry vs. placebo. Commercial source of elderberry syrup unclear (could have been produced as part of study?)
- Subjects were permitted to take antivirals and flu shot
- No statistically significant difference was seen in reduction of symptoms between elderberry vs. placebo groups over a 2 day observation period.
- Limitations: Placebo and elderberry groups were not randomized with respect to use of antivirals and/or flu shot, and there was a significant difference between the groups regarding those variables. Authors stated that this should not have affected results, but this essentially took away the study design’s benefit of randomization. Also, the study changed inclusion/exclusion criteria midway through, and data collection also changed, so some analyses only included partial data. Lastly, study was only powered to detect differences after 2 days, even though cited literature saw differences after 4 days.