Expert: Jessica - 10/7/2011

Question
Hi Jessica:

We've got a two-year-old mixed named Fancy. A few nights ago, she had two grand mal seizures within about three hours of each other. We took her to the hospital (where she had a third) and admitted her. They sedated her and put her on phenobarbital and kept her for about 24 hours. She's back home now, but she appears to experience petit mal seizures every 15-20 minutes (eyes dilate, she begins to shake and breathe rapidly, followed by an odd head movement and a very loud series of yowls. She then returns to normal until the next episode.

Is this frequency of petit mal seizures normal following a series of grand mal seizures like she experienced? She's been on the phenobarbital for about 36 hours now. Will this treat the petit mal seizures and, if so, about how long does it take for it to fully get into her system?

Thanks so much!

Answer
Hi Jason,

It's uncommon for idiopathic epilepsy (meaning epilepsy that has no underlying cause) to result in such frequent seizures. Most cats will only have seizures a few times a month, or a couple times a week at most. But multiple times a day, and even every hour, is disconcerting. Seizures at this frequency usually indicate that there is some root cause. I imagine that the vet has taken blood samples and is running tests to see if any infectious diseases might be the cause of her seizures? Did they run x-rays? Causes of frequent seizures can include infection with toxoplasma or Feline Infectious Peritonitis. Cancer is another major cause of persistent seizures. Toxins can also cause seizures, and this includes toxicity from many flea treatments.

But if this IS a case of idiopathic epilepsy, it can take a couple of weeks for the phenobarbital to have much of an effect. The dose may also need to be tinkered with. If she doesn't respond to the initial dose after a few weeks, it will need to be raised. Some cats are rather resistant to it and need to have it raised a few times before their seizures are well-controlled.

I hope she's feeling better soon!

Jessica