You know those drops they put into your eyes at the eye doctor, the ones that dilate your pupils? The dilating stuff is called atropine sulfate, and it’s extracted from the Atropa belladonna plant (known as deadly nightshade). I don’t know about you, but I hate the sensation it causes. My eyes water like crazy when I go out in the sun, and I can’t read for hours afterwards.

But many Italian women of the Renaissance willingly used a derivative of the belladonna plant as eye drops to dilate their pupils, believing it made them more attractive.

Atropa belladonna is a flowering plant that grows all over Europe. The foliage and berries are very toxic, containing tropane alkaloids that have long been used as poisons. Before he became king of Scotland, Macbeth, who died in 1057 (yes, the one Shakespeare wrote a play about), was said to have used it to poison an army of invading Danish troops.