Constrict those vessels!

From what I've read, the trick to diminishing the appearance of dark eye circles is to constrict the blood vessels under your eyes. Something cold would do, like a cold metal spoon, cold teabags, and cold cucumbers.

If you want to walk the chemical-ish path, then use caffeine (It constricts blood vessels). Or get creams for hemorrhoidal treatment. Yes, yes. Everybody knows about that. But there are active ingredients in the cream that helps eye bags and/or dark circles. So they might as well just take those ingredients and make it into their very own eye cream, right? Why want to use something that wasn't meant for your eyes on your eyes???