Dog seizures

Our 12 year old Ridgeback Cross started having seizure last December. Took her to vet and they prescribed Levetriacetam. Seemed like it worked but had to increase dosage to 3 times a day 750mg at a time. Has had 2 in the last two days. Anybody else had something like this with your pet. Sure don't want to lose her but can't stand to see her go though this.

Seems like big doses for a dog. Big dog?

70 lbs, They say 20 mg per kilo and I done the conversion and its even higher. I hope for the best as it doesn't seem to be working as she had another one last night.