Menthol eye drops

The worst part about not speaking the language here is that I can never read ingredients.  I always try and see if there are dairy products in the foods I eat, but it's so hard to do it here!  In languages like Spanish and French, even German, you can make out the words with some form of 'milk' in it.  Here, it's nigh impossible!  I'm leaning some of the katakana for 'milk' and 'butter' but it is still tough.

The other day, I tried to buy contact rewetting drops.  Now that was even harder.  I picked up a small bottle that resembled drops and brought it to the counter.  The pharmacist of course did not speak English.  I gestured with the drops into my eyes, and she quickly shook her head and took the bottle away from me, indicating that these are NOT for the eyes.  Whew, relief.  

Then she introduced me to a pharmacist who spoke a few words.  I gesticulated wildly and got across my point.  He said, "soft or hard?"  I replied, "soft."  He brought me over to some drops, and I chose a blue one with the words "Cool" on the label.  OK, so far, so good.  

When I stepped outside, I immediately put the drops in my eyes.  This, my dear reader, is where you should learn from me.  When you have no idea what you are putting into your eye, only do ONE EYE AT A TIME.  That way, you don't blind BOTH eyes!  As for me, suddenly both of my eyes were stinging and I could not keep them open.  I hoped this was not bad for my vision.

Later, Jeannie and Cat informed me that these are 'menthol' eye drops.  Illegal in the US.  They give your eyeballs a "refreshing blast of minty goodness."  Here's an interesting review.  I also read that they have great whitening (redness relieving) abilities, especially good for people who are stoned.

Anyone else try and use these before?  Now I'm scared.  Ophthalmologists out there?  Help me out!  Are these detrimental to my eyes?  I wish I could read the packaging inserts!