Our lab started having seizures in April 2009 when she was 5 years old. I immediately took people's advice on this website to monitor her diet. Through a process of elimination of trying different, healthy dog foods, we found that she was highly sensitive to products with Rosemary... Even a cracker that she picked up off the floor catapulted her into seizures. So we took her off of dog food with Rosemary. Things got much better, but then she started having cluster grand mal seizures later in the fall and it had gotten to the point where she was having five seizures in 30 hours... Absolutely horrible! We completely eliminated dog food and dog biscuits from her diet and she has been seizure free since April of 2010. We determined that she was sensitive to the processed corn in dog food.
We feed our lab raw chicken legs (not cooked because the bones splinter and are dangerous for them to eat), one in the morning and one in the evening as well as other raw or cooked meats. We also feed her many different foods that we eat... Raw carrots, cauliflower, green beans, cottage cheese, boiled or raw eggs, pastas, rices, breads, baked or mashed potatoes, and many other fruits and vegetables that are not toxic to dogs. We mainly avoid leftover dishes that have too many spices or onions and such. I keep a list inside a cabinet door in the kitchen to remind me on what she can eat. As a result, we have a very healthy, happy lab. It's a little more work and maybe a little more expensive, but we no longer have the stress of watching a family member suffer. Plus, she is at a healthy weight because dog food can be very fattening. I urge you to not put your dog down or feel like you have to spend so much money on vet bills and meds, unless it is necessary. Most likely, it is caused by something that they are ingesting, so please look at that first. I hope that this helps.