I had no idea that it was a common thing in Japan to use minty eye drops (see this page on j-list for a couple of common brands, about 4 or 5 products down the page). I picked up a bottle of Sato Flash eye drops at Mitsuwa Marketplace this afternoon to try 'em out. I needed a pick-me up cos I was out and about for school from 8:30am till 9:10pm! canadadrugs.com
These drops that I got have menthol & camphor in them, I think. WOW, these things refreshed my eyes and made them all clear and white. I'm amazed. Yeah, so it stung a little at first, but it worked!
Whodathunk... mints for your eyes!