Some time ago, I was given a 2" Meade EP which had been oversprayed with sunscreen. The sun screen ate into and destroyed the coating on the EP lens. I tried a few different things unsuccessfully, but in the end I tried the offender anyway, and used some sunscreen to remove the remaining coating. Optically it is fine but obviously the performance of the EP isn't what it once was.
Use this information at your own risk!
Al.