Eyebright's medicinal properties date back to the 14th Century during which it was believed by some to 'cure all evils of the eye.' Eyebright is high in iridoid glycosides such as aucubin. In several in vitro investigations, this constituent has been found to possess antimicrobial activity. NOW® Eyebright 410 mg uses the whole herb powder delivered in easy to absorb veg capsules.