Hi, Ann. I have had six or seven shots of Synvisc in each knee the last few years. I do not have any adverse reactions to the shots. They just help me stop hurting. I don't know if there is supposed to be a limit to the shots, or not. I imagine that depends on the individual patient. My ortho says I have had more of these shots than anyone else in his practice, and he will continue to give them to me as long as they keep helping.