sheezit,
I don't like the mechanism of action of Prolia. It is an antiresorptive. So it collects old bone and prevents the normal process of remodeling the bone. It holds osteoclasts the last stage of development. In doing so it collects they call it a resevoir of premature osteoclasts that are released on to the bone in a flood of acid when Prolia is discontinued
Osteoclasts (you may already know) are the acid producing cells that prepare the bone for the osteoblasts--the cells that lay down new bone. Our bones remodel all the time according to our activities, acutally laying down spicules in the best direction to remain flexible with the type of impact our activities generate.
In most patients Prolia protects the bone from frature. In some it causes fracture. And in all who don't replace the drug or are late for the subsequent injection, it wreaks havoc with multiple fractures. After Prolia you are recommended another drug that will tampen down the osteoclasts. These drugs continue to preserve older bone, slowing the process of remodeling.
Then there is Forteo. It's drug that builds bone, as does Tymlos. I think they are both wonderful drugs. They encourage remodeling and don't have any black boxes.
I've been on Forteo for almost a year without side effects, except that my fingernails are stronger.