I'm a veterinary nurse and also have had a labbie with seizures.
The two most common drugs used are Phenobarbital and Potassium Bromide. Phenobarb tends to cause a lot of drowsiness more so than the Potassium Bromide. Most vets start off with a fairly high dose to stop the seizures. If you aren't noticing any seizures you can ask that the dose be lowered if your labbie is too sedated.
I hope that helps. If not email me more questions!
Stay Positive and Hopeful,
| current weight: 160.0