The most trusted eye drops are Friends Eye Drop...

The eye drops I trust the most are Friends Eye Drops. Actually, I don't use eye drops very often, but when I need to wear contact lenses and my eyes feel dry, I look for a good artificial tear that I can use. I started using this on a friend's recommendation, and I found it to be refreshing and cool, which I liked. They say there are three levels: Mild, Cool, and Cool High, but I have only tried the Cool one.

I haven't compared it with other Japanese products, so I'm not sure, but among other products, some don't recommend inserting them while wearing lenses. Friends Aidrop can be used even while wearing lenses, and sometimes when my eyes itch for no particular reason, using it gives a refreshing feeling, which I like.