I go every three months for injections. I have two different PM docs and one told me the only way to control ON was to get the injections every 3 months. I told the second PM doc what the first one said and he finally started doing it and I'm in better shape than I was previously. Right now I'm not doing too good, but I'm less than a month out from my next round of injections. Get your PM doc to schedule them every 3 months and see how you fare then. I still have the headaches and the pain, it just doesn't seem to get as bad as they previously were. Best of luck to all of us that deal with it.