I have a client that comes in every week to get tattooed and he uses it every session. It works great for him, he feels nothing for a couple of hours BUT if he applies it more than a half hour to forty minutes beforehand the skin gets hard and the color doesn't go in as well. It's like the skin becomes engorged with the shit, leaving little room for ink. So, that being said, Dr Numb works wonders if it is used correctly. Also, put plastic wrap over it when it is on the skin, I think it loses its effectiveness if left to dry out.