Are injections safe and proven beneficial?

Firstly, I would find out my t score because severe osteoporosis would,have to be more than -5 as I have -4.3 at the base of the spine and I do not call that severe. 

My GP is the first to admit she does not know everything as no GP can, not even a specialist knows everything!

I would hesitate and research and ask other people their experiences.

I take none of the drugs because I do not trust them.

The decision is yours and yours alone but you need to be sure and well informed. So pause and take time to know what is best for you.

The major concern about all of the osteoporosis drugs is their exceedingly long half-life -- they can remain in the body for up to ten years. So side-effects are not necessarily reversible. There are two potentially catastrophic side-effects to all of the osteo drugs (excluding Forteo, which has its own set of warnings): atypical femoral fracture, whereby the "new" bone, which may be denser but more brittle than the "old" bone, fractures with little-to-no impact; and osteonecrosis of the jaw (ONJ), whereby tissues in the mouth fail to heal after dental procedures. The medical establishment claims these complications are "rare"; however, data continue to accumulate as longer-term results become available for the many thousands who used to be put on the drugs by their doctors indiscriminately even though they only had osteopenia (which is pre-osteoporosis and doesn't necessarily develop into osteoporosis). My own opinion is that the dismissive label of "rare" isn't going to have credibility much longer.

That said, severe osteoporosis is worrisome as well. I can appreciate the difficulty of the decision you're facing, as even with what is probably classified as mild or at most moderate osteoporosis (for spine, not hip [so far]) I've felt very stressed by my decision to not take these drugs due to pressure to do so from a number of doctors. It goes against the grain to *do nothing*. I know that posters have tried natural methods such as exercise and dietary changes, and some believe that this has helped. In my view, there's really no way of knowing whether alternative approaches do much of anything. In fact, there's no way of knowing if the drugs work either, as all that can be measured are changes in bone density yet increased bone density does not necessarily prevent fracture from a fall. (Most people who fracture a bone do not even have osteoporosis.) Possibly the drugs exert a protective effect from low-impact fractures .. that is, fractures that would not have ordinarily occurred, as they happen in the absence of trauma. (But I'm just speculating about that.)

I believe it's extremely important that you know exactly what you've been prescribed -- you do not mention the name of the drug in your post -- so that you can research it yourself and raise any questions or concerns with the doctors. Make sure you know what red flags to be aware of if you do proceed with the injections so that you can get any problems addressed and go off the meds as soon as possible, should the need arise.

Best of luck with your decision.