Well, this is how I saved mine at least.
Coupla things about cats, I didn't know:
-if your cat has a plugged nose, it will not swallow. They will breathe through their mouth when this happens. If you see this, your cat is in danger.
-if your cat cannot smell it's food, it won't eat it. The food must be known good food and this happens by smell and taste for a cat. Smell is obvious, but taste can be problematic as the cat must actually try the food in order to taste it. This is a chicken and egg type problem your cat will need your assistance with.
-cats can only go a coupla days without food and water before critical systems begin to shut down, causing other problems.
-Afrin type nose drops work well on cats. One to two small drops per day, one nostril only. Alternate nostrils daily.
Essentially what happened to me was my cat ended up with a very bad cold. Completely plugged it's nose and sinus. Some fever, but all in all, it really was just a stuffed head. I tried vapor, cleaning the nose, etc... Nothing worked until I tried the Afrin. (And I did look up the toxicity before. Just so you know, most human cold remedies contain highly toxic elements for cats. In many cases, the toxicity level is many times that for us humans.)
Life circumstances did not permit a big vet bill. Sometimes you gotta make choices and this was one of those times. So, it was up to me and the cat to see how this was all going to go.BTW: I should put the standard disclaimer that by reading this, you agree to hold me harmless for anything that should happen. I'm relating a life story only, and I could not see a VET for a lotta reasons. Go see your vet if at all possible.
So I started reading about cats, and their picky nature. That's where I got the info tidbits above. One other thing is that the mechanical problems caused by disease that affects their head usually is what does them in, due to the fact they won't consume the water and food necessary for the other healing processes to work properly. If they can eat and drink, you've a high percentage chance of their body being able to fight off the disease itself. That's where the cat and I were at. Not pretty, but not impossible either. Better than nothing and a certian death for sure.
By the time I reached this understanding, it had been a coupla days. Clearly getting into the danger zone. I started with the Afrin, then had to give the cat water drop by drop, using a small syringe with a pointed nozzle. If you surround the cat, then nudge the nozzle in to the side of their mouth, you can do a small squirt and let the cat struggle through getting it down. I did this a lot, many times per day, for a couple of days. Sometimes I would take some broth and use that for protein. Watch the broth though, it can get sticky and cause other problems. Best alternate with water, then broth, etc... always end with water.
A great check for overall cat hydration is to scrunch up the skin at the back of their neck. When you release it, you learn something about how hydrated your cat really is. If it snaps back quickly, you are in good shape. If it comes back slowly and does not regain it's usual shape, then the cat is not properly hydrated.
After a few days of this, we managed to hold our ground on hydration, but were losing big on protein. I was puzzled after getting her nose clear enough to breathe. Thought I was largely home free, but the cat would not eat! I tried a lot of things, but nothing worked. She would look at it, noze it, lick it, and that's it.
So, time to really annoy the cat. Time to force feed. Another Internet search led me to a great technique that worked very well. The bottom line is the cat wants to eat, but needs to be convinced that it can eat and that the food is something it should eat. Not an easy task.
Surround the cat again. I did this by crouching over the cat, trapping it between my legs. Then put some baby food, on one forefinger. With your other free hand, squeeze where the jaw hinge is and the cat will open it's mouth. Quickly (and I mean quick!) scrape a small amount of the food onto the roof of it's mouth.
Too slow and you get chomped! Too fast and you don't get the food in. Good luck!
What's going to happen is the cat will taste the food. It's gonna be very upset at you putting it there, but it will eventually figure out that either:
-you are gonna keep putting food in and it realizes it is just gonna have to deal,
-it knows the food is good from taste,
-it realizes it can actually eat the food!
Eventually it will try to eat on it's own as that is much better than dealing with you doing the feeding. Sounds brutal, but it works fast! That's something positive at least. Trust me on the feeding, it's largely negative. Took my cat two times through this whole affair and it licked the food off my finger the third time, then tried the food on it's own the fourth time. Each time though I had to go the distance. Crouch 'n trap, get the food ready, squeeze the jaw, etc... The cat has gotta know this is just going to absolutely happen.
Amazing! Just fricking amazing how picky cats really are. Everything else I tried failed totally and completely.
Texture seems to play a big role. Anything gritty won't fly, so don't bother mashing up cat food. After working the baby food for a day or so, I tried various things. The winner ended up being frozen shrimp. Put a few of these on a plate and nuke 'em for long enough to melt the water off and or nicely warm the shrimp. Leave the water on the plate as it's tasty to the cat. Strip the tails, if there are any and chop the meat up into nice little bits. Mine would work though the shrimp slowly, then lap up all the water, then sleep for a long time.
It took a few days of the shrimp diet for the cat to recover enough to start just drinking and eating on it's own, but it did and is just fine today. If you reach this point, just keep offering moist food and watch your cat for signs of improvement. Make sure water is fresh and take it to the bowl often to see if it's ready to do it's own thing.
Ideally, you can see a vet. If you can, do! Of course, that goes without saying, but this is the Internet and you never know...
Hope you don't end up in this situation, but if you do, maybe some of this will prove helpful!