Hello I am Dr. Joey. Thanks for trusting me to help you and your pet today. I am a licensed veterinarian with over 16 years of experience. I look forward to working with you.
Regardless of the exact diagnosis for the new seizures Scruffy is experiencing, he must go back on an antisiezure medication. You do not necessarily need use phenobarbital again, which although predictable does require much more blood monitoring than most of our other medications we now use for this problem. You need to discuss this with your veterinarian as soon as possible. These seizures are too severe to continue to just watch.
As well, if you want to achieve a diagnosis, then I highly recommend you ask your veterinarian for a referral to a neurologist. He is going to need some testing which might include advanced imaging of his brain (MRI) and a cerebrospinal fluid evaluation. I am assuming you already had repeat screening lab work within the past few weeks with your veterinarian since onset of seizures to rule out easy causes such as liver disease, toxin exposure, and infections (fungal, viral, bacterial). IF not, then this is a starting point with your veterinarian.
As a side not, I do not know that we can rule out epilepsy so definitively. Sure it is odd that he went so many years between seizures. We have no test we can do to diagnose epilepsy. It is a diagnosis of exclusion, which means we rule out everything else and end up with this as our diagnosis.
I am at a point I need to know what questions you have. I hope that the information I provided has been helpful.
Please let me know if for any reason you need further clarification, have more questions, or were expecting a different type of answer.
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