I guess the reason I post is to demonstrate a variety of experiences, not to advocate for a particular choice.

Tymlos was approved April 2017 by the FDA. Forteo in 2002 (generic version 2023). Evenity in 2019.

From Save our Bones:
(Tymlos) activates the same parathyroid hormone pathways as Forteo (teriparatide), and thus functions in the same way. The key difference is that while Forteo is a recombinant human parathyroid hormone analog, Tymlos is a human parathyroid hormone-related peptide analog.

I have wondered whether the difference in mechanism accounts for some of the dosage differences. I liked Tymlos because the dosing is adjustable. I have seen studies that Tymlos is slightly better for spine results. There are comparison charts and the two are pretty similar in results.

@ninglike I have no idea why I could not tolerate Forteo. I went to an immunologist to get desensitized and she basically said my immune system had "gone awry" and that we had failed. My heart sped up, I was out of breath and felt extremely faint, and I had icy stabbing pain in my lungs. Most people don't have this. As I wrote elsewhere I even tried a 10% dose at home (my doctor was amused) by shooting a dose in a sterile cup and using my kid's insulin syringe to draw up 10%. Same problems so not dose dependent. May have been an allergy.

Full dose Tymlos was also tough to handle but I went back on at 20mcg and moved up slowly, eventually staying at 70mcg (full dose is 80). If you don't do a full dose, you do need to refrigerate it so it will last longer, and you need extra needles.

It makes no difference which you choose honestly. Flip a coin! @gently and I are a tag team. She posts Forteo and I post Tymlos, maybe cancelling each other out but letting you know that this decision is not a crucial one in terms of these two drugs.

I really only planned on doing Evenity for the stronger bone-building months (4) and wanted to still have some months left (8) for the future. That said, my doctor was on board because I had some burning sensations that were difficult. I have lupus and high antibodies to scleroderma and have a 20 year history of neuro sensations so this may have been particular to me though a couple of other people have mentioned it. Note I had already done two years Tymlos. Most people do fine on Evenity with few side effects (and tend not to come on forums!).