[used to be]

Hello to all and hope all is well. I was wondering how many unsuccessful nerve blocks should you have before you move on to something else. I had read on one of the rsd websites that if you have no success after 3 blocks that you should stop otherwise you could do more harm than good. It is hard to know what to believe because there is so much contradiction between 1 rsd site and another. What do you all think and what has your experience taught you? Thanks Jeannie