Hi,
If Thomas hasn't eaten, drank or gone to the bathroom for a day or more, he needs vet attention IMMEDIATELY or you may lose him! If your cat doesn't eat for a couple of days, he will develop hepatic lipidosis
The ear symptoms do sound like either an ear infection, ear mites, or a yeast infection and any of these must be treated with prescription medication specifically for the condition diagnosed.
What condition was the Dermagen prescribed for a year ago? Did Thomas have the same ear symptoms then?
For now, you can try to alleviate his discomfort by cleaning out his ears with a cotton ball dipped in mineral oil. You HAVE to get him out from under your bed and get some water or children's unflavored Pedialyte, and some food, into him by dropper or syringe, if he won't eat on his own.
First, give him one dropper of a water mixture of 1 cup water with a dash of salt and sugar (if you can't get the Pedialyte, which is preferable), every ten minutes for an hour. Then, water down some canned cat food or plain chicken baby food (with plain water) and give this to him by dropper every 10 min. for an hour. Then, repeat the water or Pedialtye again. If he vomits, STOP!
If you have a vet ER center nearby, please bring him in NOW. I would not use a year old medication like Dermagen at this time, until his other symptoms are evaluated and treated, and the vet tells you what the problem is with his ears, and prescribes the correct medication (even if it IS Dermagen again; it will be 'fresh').
Good luck! I hope Thomas will be okay and please keep me posted on his condition and the vet's findings. Thanks!
Cher
If my answer is helpful please click ACCEPT. Click reply for more info. Please talk to me before considering leaving neg. feedback; my only goal is to provide helpful answers. Thanks!