My endo has told me that he wants a round of labs 2 weeks after my stopping Tymlos (to see where CTX is) and then wants me on ReClast not longer than a month after my last Tymlos shot. He then wants to see labs (CTX) again 3 months after the ReClast infusion and hopes it will have dropped my CTX by 50%. Hope this helps..... good luck. Move quickly! (And I have read in Dr. McCormick's book "Great Bones" that regular bisphosphonates are not strong enough to prevent the rebound coming off the anabolics (teriperatide and Tymlos) and it needs to be ReClast which is much stronger.