On Forteo 18 months - high CTX?

I have never had any of the bone marker tests that you mention. I see Dr. Mannstadt at MA General. I am on my third year of taking Forteo, my second year was up in July, and have been approved for a third year.

Good morning @cat30064, fellow Forteo user here. At which month of Forteo treatment did you have Dexa scan? If your Dexa includes TBS, do you see any improvements with its scores? May I ask the cause of your osteoporosis; was it due to primary, idiopathic, or a secondary cause? If due to a secondary cause, was the underlying cause reasonably controlled during your treatment? Thanks

24 mos of Forteo. My Dexa did include TBS. I had no gains on Forteo, but remained stable at -5.00
Feel confident my Osteoporosis was exacerbated by SIBO and the lack of absorbing proper nutrition for about 1 year.

I had my DXA at 14 months. No TBS software. But 2 years ago I had a REMS (Echolight) scan that showed good bone strength. My cause of osteoporosis is most likely age, no parathyroid issues. I will be 70 soon. I’m conflicted whether to stay on Forteo or try Reclast.

I do have gut issues. Slightly low gamma part of vit. E. Vitamin D is at 38. I do suspect though that I have some issues absorbing some minerals. Although everything tested so far has been in the normal limits.

@cat30064 i wish I have monitored my bone markers like you did as I definitely am planning on more rounds of Forteo. Curiously, were other treatment options after the completion of Forteo explored by your endo?

@cat30064, thanks for posting your numbers. I find it fascinating that CTX jumped so high, but also that it is only now coming down. It appears that you are having a delayed response. Can I ask if you were on bisphonates before beginning Forteo or Prolia. I would be wanting a third year of Forteo.
At this point in your care your D levels would be low because Forteo is very good at using it. I tripled my intake of D3 at 14months as it had gone from 70 to 30. I like mine at 70. 50 to 70 is often recommended with osteoporosis.

It's my understanding that the lower the number, the better regarding CTX.
Is that correct?

@midwestgirl
I've been waiting for someone wise to answer your question, so I could read it.
Because higher numbers represent more bone remodeling, it might be best when both CTX and P1Np are high. The tricky part is the ratio.
Decades ago there weren't medications that increased P1NP. Osteoporosis medications could only moderate the bone breaking down. So lower CTX was considered better.
But you need the bone to be broken down where it is weak so it can be replaced by stronger, unfissured bone. As CTX represents that clearing of older bone and P1NP represents the laying down of strong bone, I want high numbers of both working on my poor bones.
While I recommend questioning all of my suppositions, I offer one of my favorite videos which doesn't prove any point. https://www.youtube.com/watch?v=Cd0YT-OV97c

I assume you are taking Forteo because you have severe osteoporosis (t-score of -2.5 or lower, especially in the lumbar spine where Forteo is most effective in improving bone density).
If you haven't had any bone density gains with Forteo, could that mean you are a non-responder or poor responder to the medication? Personally, I wouldn't continue on Forteo if I weren't responsive to it -- it's a big outlay of money. (I know, I was on it for 24 months, with a 14% gain in spine BMD.)
What does your doctor/endocrinologist advise?
Maybe consult with another medical professional, e.g., Keith McCormick ("Great Bones" author), Lani Simpson? Also, make sure your DXA scans and comparison were performed properly and are accurate?