Cat is weak & not breathing well

Our 4 year old black & white tabby hasn't eaten much over the past couple of days, and today he is very weak. He isn't drinking any water, either. When I got home from work tonight he was slumped down on the floor, and his eyes are glazed, kind of staring. He is having difficulty breathing. We called all around, but nobody can see him until the morning. In the meantime, we have given him some fluids using a straw as an eye dropper, and that seems to help a little bit, but nothing that looks hopeful. I'm worried about him over the next 8 hours before the vet opens.

Any help would be greatly appreciated. Is there anything I can give him, medicine commonly found, anything we can do?

There should be an emergency vet in your area, please find them and take your cat in tonight.

You really shouldn't wait on this. Wher are you, maybe there is someone here that can help you out to find a place to go.