Where this leaves the stack BPC-157 and TB-500 are the two most-researched tissue-repair peptides, and the reason they are paired is a real one: they do different things, at different scales, through different mechanisms
If transient proline metabolites were dangerous, every meal would be toxic
For example, for a patient with shoulder pain, he will perform a hands-on osteopathic evaluation, correlate it with the ultrasound imaging, and tailor a treatment plan that may include PRP, peptides (like TB-500 or BPC-157), physical therapy, and supplements rather than jumping to surgery
In practice, providers may advise against NAD+ injections in patients with serious underlying medical conditions as a precaution