HI Sandra,
There are no clinical trials to say how many courses of shots a patient can take, and what their long-term safety might be. However, in many cases, we do repeat the series of injections in patients whose symptoms return. I don’t know too many docs who do it more than twice but it’s not something I’ve inquired about much in community practice. Sometimes a steroid injection works just as well, and it is only one shot and can be given about 3 times per year.

