I used to think Bacitracin was ok to use for tattoos also, it isn't. It is NOT OK to use because it has painkillers in it and it can mess up your tatoo. Painkillers can actually pull the ink out of the fresh tatoo and well... you see where I am going with that. You are only suppossed to use regular A&D ointment on a tatoo and that is it.
As for the snake just use polysporin. This animal is much smaller than we are and using a painkiller on it could potentially overdose it. Plus some animals just don't react well to it certain medicines. Like how you are never suppossed to give a dog ibuprofin(motrin/advil etc...) for example.
Edit: Also for the OP, if you are so worried about this why not try and convert to f/t? Unless you breed your own feeders its alot cheaper and easier for you(and the snake) and obviously much safer.