Echinacea is a flowering herb part of the daisy family.
It is used mainly to ward off infections like cold and flu, but does work for any time you are just not feeling up to the mark.
I find it very helpful. I work in a UK owned bar, we have a lot of customers who have come over from the UK and they usually bring the infections with them, I take start taking Echinacea before I start work , and this usually keeps me cold and flu free so that I can do my job.
You can now buy Echinacea almost anywhere and it comes in tablet, liquid and even tea form.