Hi, @gently -- we meet once again! Thank you for this info. I believe the same thing happens with Tymlos -- after 1.5 years, its effectiveness wanes (the Tymlos company chart has a chart). And I suspect that the osteoclasts start taking over, because Tymlos also increases their activity. I'm not sure I understand what you are saying about cannulation -- so cannulation is good? decreases fracture risk? I would think it would increase the fracture risk. Once I finish with Tymlos in December, my endocrinologist said she would start doing the bone markers. (My rheumatologist has been doing the markers meanwhile.). I'm assuming that would be used to monitor what the osteoclasts/osteoblasts are up to. Is there a ratio between the two that is good? I think I read someplace that the ratio should be something like 10 to 1 -- that is CTX 10 times more than P1NP.