My most recent beloved Sheltie princess developed a seizure disorder.
When she was older, around 11, she progressed into gran mal seizures. Terrifying.
Initially, she would have small seizures, largely brought on by being in the heat.
With her small seizures, if I caught the onset early, it seemed giving her frozen green beans helped to bring her back from the brink.
Also, afterwards, even with small seizures, she would have an "aura" after. For her, it manifested as terror of her large water bowl.
She was not on meds until later in life.
The danger is with tremendous heat resulting from uncontrolled seizure activity.
She had a bad episode while my daughter was at work. She rushed her to an emergency ICU vet where shd received 1 on 1 care 24/7 for a week or so, to the tune of >$5k.
Afterwards, she needed go relearn how to walk. She only lived about 3 more months. Her time came on xmas day & vet helped her to the Bridge.
Diet can be a factor, as can antiparasitics. Was dog exposed to Seresto collar??? Biggie!
I hope this was helpful. Please feel free to pm if you have questions. 
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