Anyone know about laser tattoo removal?

I’ve done it before but I still need a few more processes and I’m going today for my monthly, a while ago the dr that does it sold me lmx5 cream to help with the pain during the process because it’s near my chest and really sensitive and painful, I was going to use it today before I go but I don’t understand what I’m supposed to do with it, im not supposed to have it on during the process either and it seems kind of weird to of sold me this cream? Idk help if you can, thanks