Yes, you need to bookend it with another drug, a bisphophate, for example, when you go off it. All my MDs want to move me to Prolila, yet I hesitate. So far, I am fine with my bisphophate - no bone issues. They note that as I am going into the "aging rapidly" phase of life, I am almost 70 now, that Prolia will have been the smart move, looking in the rear view mirror. Mayo Clinic's webpage on either Prolia or Osteoporosis says something along the lines that Prolia is for severe or hard to treat osteoporosis. I am still mulling thing over. I don't feel I am severe yet. And I think MDs really like Prolia. For me, it is less invasive to take a weekly pill than to remember, upon pain of massive bone loss, to hike in for an injection two times a year.