My cats have URI

Question
i recently adopted a kitten from my local aspca, a cutie he is, two after the adoption he started sneezing, so i took him to the vet and the vet said he has URI. Because it is contagious it has now spread on to my other adult cats. My 9 year old siamese and my 5 year old American short hair.
I took my siamese, to the emergency clinic and is now on clavamox and lysine. My american short hair is sneezing so im giving him clavamox. but here lies the problem, my siamese is still not eating, he does drink and use the bathroom. but not eat and it fustrates me. the doc said he has mouth ulcers, prior to the kitten he has had no illness what so ever, the kitten has had his shots. im at a dead end, its a battle every morning and evening giving him the medicine. he puts up a fight and he is a very strong cat it takes 3 of us to hold him. is there a way i can get him to start eating?
when i took him to the vet, they gave us two options the conservative way ( water treatment under the skin) or the aggresive way which is blood work. But finacially i cant afford the aggressive way. I bled my bank account dry just for the water treatment. i need help with him, im scared.
any advise

Answer
Sometimes it can sure to be a struggle to get a stubborn cat to eat when it is not feeling well.  I am not sure what you might have tried already, but cats are very dependant on their sense of smell to stimulate them to eat.  When their respiratory passages are stuffed up with a URI this can cause problems.

At this point a good thing to try might be baby food, such as chicken that you warm.  Warming the food brings out the scent and can entice even a stubborn cat to eat.  Additionally such foods have a good amount of moisture in them which can help with the hydration.  The fluid that was given to him under the skin was to help hydrate him.

I hope this suggestion will help.  Best of luck to you and your feline friends.