My dog Bingo was diagnosed with epilepsy when he was about 2, the vet gave us a prescription of phenobarbitone one twice a day. Bingo only had maybe one attack a year, he would whine persistently for no reason just before he started to seem to go wobbly and bump into things, then he would keel over, his eyes would stare and his legs would go rigid and straight , sticking out 4 different ways so he was lying on his chest/stomach and looked like he had collapsed. His tongue would hang out and he would wet himself.
We were told not to crowd him, not to move him, just let it pass. It was scary, Bingo took around 5 minutes to recover and always wanted a drink of water straight away after the attack.
I had Bingo put to sleep last August, he was nearly 15 years old and had lost the use of his back legs due to a spinal tumors. He was a great dog and I miss him.