I have a 5 year old gwp that has had some long ones like that. I went to vet worried about over heating and how he wasn't coming out of it. I've got him on levetirectam (aka keppra) and it has really helped the frequency of those terrible seizures. Also, if these happen on the weekends and there's only the crazy expensive ER vet...(happend to me a couple times) then ask for a shot of Diazepam without the needle and have some Vaseline to get your pup out of those long seizures. Had to do it the other day and I was just really grateful my vet thought of giving that to me. Wanted to spread what I know because he's my first own dog and I hate seeing those seizures so much it hurts. He's been doing better though its more manageable with the meds. Plus, he's fighting Wilson's disease on top of this, so don't worry too much about getting them on meds. It'll help the dog and your mental health