After vet visit advice

My cat a few years ago was thrown into diabetes after being given a steroid shot. He went into remission from that as his pancreas kicked back in which they say can happen in cats and not people. Took him to the vet Thursday because of vomiting. They say he needs to go on a hypo allergenic diet. And they updated his rabies and distemper shots. Gave home a B12 shot and a acid reflux shot. It is now almost 48 hours later and he is not himself. Depressed almost zombie like. Could these shots set him back to diabetes. When will this wear off?

I'm not sure. Please call the Vet and see if they will pass you through to the Vet on call.

Will he eat anything in the mean time?

Yes he's been eating the samples they gave us. And drinking.

The rabies and distemper shots could make him feel bad for a day or two, that's not uncommon. IMO he shouldn't have been given vaccines when he was already unwell. I know some vets don't think it matters but from what I've seen, it can make them feel worse. 

As long as he's eating, drinking and using the litterbox, I would wait and see if he comes out of it on his own. I don't think anything he was given would cause diabetes.