I first started dealing with this 4 years ago. My momma cat had kittens. All seemed healty up until 10 weeks, My little girl gracie started having terrible siezures, she would lose complete control. I took her to this one vet who subscribed one med after another. nothing was working to get them under control. She was eventually put down due to the severity. I had an autopsy done at Johns Hopkins , buy they turned up nothing. I had the autopsy done because her brother "piglet" started with the siezures. I wanted to know what was causing them. I decided to take Piglet to a different vet. Who promptly took him off all meds and put him on phenobarbital. The pheno began working and lessened the severity of siezures. Now his dose has needed to be increased 3 times to find an amount that will work. Currently his script is pheno 20mg/5ml ...3ml twice daily. he weighs 6lbs. His mother who just started having siezures 4 months ago, is twice his size and only needs have the amount to keep her under control. My vet has presumed epilepsy, since all other test have been done, and everything turn up neg. There is no test for epilepsy. It is common to see it in cats over 4 years of age. Piglet is a strange case, because he was so young when they started. Phenobarbital can do damage to the liver, that is why a lot of vets try to avoid it. But it does work. I figure it is the lesser of 2 evils. As far as caring for an animal with siezures, It is extremely important they get their meds on time every day. Phenobarbital takes 48 hours before you will see results. If you cat can not come out of a siezure say within 3 minutes, and keep shaking. They must be rushed to the vet within 30 minutes to avoid permenant brain damage. Usually diazapam is injected. when they are having a siezure wrap a blanket around them and try to hold them still. They could cause a lot of harm to themselves. especailly bitting their tounge or paw. Me and my cats stay together at all times. Piglet has learned to walk on a leash. His mom who has started with the siezures , I bought a stroller for pets. It is completely enclosed. I have been taking piglet with me everywhere over the years. I have a pet bag I carry that looks like a purse , I put him in it when I go shopping. He has become a good friend. He has suffered some brain damage. He does not know how to do a running jump. He could before the siezures. So he has lost some motor skills. But you should see they looks we get when we go for a walk. Piglet walks on the leash better than my dog. If you need to talk, or have any questions, just post back. would be happy to hear from you.
EDIT* I just wanted to add, cats with siezures can not be operated , or have teeth cleaned. The drugs they need to use can increase siezures. So you must clean their teeth daily.