I use contacts that are good for about 2 so my dr says. I usually use them for 4 weeks. I have done this for a couple of years. no problems. Today my right eye was irritated I took my contact out of that eye. I was visiting family. I asked for Visine they gave me some. I used it continuously for several hours. my eye continued to burn, running with out stopping and itching. I put glasses on and read the bottle the med was expired from 2007. I have flushed it out. I have used total visine not expired. It is still doing the same thing. curently have a patch on it.