this is very interesting; do you know if these shots are delivered directly to the inner ear through the eardrum (vs injections of some other kind)?
If so, that's quite interesting. I know of two different studies, one each from the US and Israeli military, which showed that into-the-eardrum ("transtympanic") injections of prednisone helped with hearing loss, though only if they were administered within a couple days. None the less, there are two giant variables here:
* whether the steroids are injected directly into the inner ear, or taken through some other means
* whether the steroids are given before/immediately following the event, vs days or weeks later
I think that both of these things probably impact the way the effect works pretty dramatically. But, to ferret that out at all definitively, you'd need a series of experiments at different dose levels where the only variable was whether the steroid was transtympanic, oral, IV, etc.
I think this is super interesting, and I wish someone would spend the several million dollars it would take to do a bunch of animal studies to try to shine a light on this and then design better human protocols based off that. As is, it's a total crapshoot if you get steroids at all following an infection or trauma, and if you do there's a lack of consistency about exactly what you get, and a lack of an evidentiary basis for why you get that.