I see an endocrinologist at Mass. General in Boston. Before starting Tymlos, he did a DEXA baseline (I have had many of course), 25-OH vitamin D, albumin, phosphorus, basic metabolic panel, uric acid. and creatinine/eGFR (kidneys). Six months later he ordered calcium, albumin and GFR, a test which I delayed and am having next week. Tymlos and Forteo can raise calcium due to parathyroid action so that is the most important for those meds in terms of safety.

I saw Dr. Keith McCormick, a chiropractor who wrote "The Whole Body Approach to Osteoporosis" and who used meds himself at one point, for a short time anyway. He recommended the Collagen CTx (resorption), PTH (parathyroid), calcium and P1NP (procollagen 1 NT polypeptide, bone formation). Mine were all normal but my osteoporosis was worse then previous DEXA and severe enough to cause 3 spontaneous fractures.

Dr. McCormick wanted a baseline in order to measure progress. My endocrinologist says these tests are not useful. Since mine were all normal, I did not pursue them since they did not seem to reflect reality. However, it may be that they could measure progress.

Dr. McCormick writes in his book that only one test of three is needed. The other one he mentions is DPD (deoxypryidinoline). It seems the other two are more common.

My doc is repeating DEXA after one year on Tymlos. There may be insurance restrictions because most people can only get a DEXA every two years. Those of us in treatment can get one annually, at least with my insurance.

I saw another highly regarded endocrinologist about 15 years ago and she did all those blood tests. I do trust my current endo but might have pushed for the CTx or P1NP if mine had been abnormal. I have stopped fracturing and feel assured that at the very least, my bone quality is improving on Tymlos and certainly hope density is too.

Once done with Tymlos, if things aren't improved enough, I want to do Evenity. If Tymlos is effective enough, I would do one infusion of Reclast to lock the gains in and THAT is when I will be monitored, and I believe for the rest of my life my endo will monitor bone loss with those blood tests (CTx and/pr P1NP) and DEXA and put me on and off meds.

The first 6 months of Tymlos have the most improvement and after a year, the growth levels off some. So I might also do one year and "save" Tymlos for later as one tool in the toolbox.

Evenity "turbocharges" (I liked that word, read it somewhere) bone growth. I took a long time deciding between Tymlos and Evenity and went with Tymlos as a first step: it has been around longer. Evenity BOTH grows bone and suppresses turnover so that was a concern too because the suppression of turnover , though less than Prolia and biphosphonates, might cause some of the same problems- too early to tell. I read that Evenity is most effective with people who haven't taken any other meds. If Tymlos works for me maybe there will be less for Evenity to do and I can save it for later too.

Just want to add that I have had osteoporosis for 14 years. I took aromatase inhibitors for breast cancer which worsened things. My doc tried Forteo for me, and my heart went crazy. Doc did not want to do Prolia, I had severe GERD with Fosamax, and doc was concerned about afib with Reclast. I did tai chi and tried to be careful. With three lumbar fractures last spring, I regret I didn't try Tymlos earlier but I never would have had this level of commitment. I came on here to try to help folks avoid what I went through with the fractures! The key for me has been that Tymlos' pen has "clicks" which enabled me to start low and ramp up carefully. Good luck!