I read that the rate of osteonecrosis is higher, and growing, with the injected or infused bisphosphonates and Prolia. The article didn't cite a study or I'd add the link. But conceptually it makes sense in the same way that injected antibiotics hit the body faster than ingested ones. And the fewer injections per year, the greater the chemical/med load per injection. I understand the convenience of getting a big dose of something less frequently but, personally, find the idea a tad alarming unless there is a totally 100% safe readily available antidote to whatever is injected in case of a problem. But that's just me.