My Frasier (gone a year now) was hypothyroid. He was on soloxine for a couple of years and had great levels. He then began having full blown seizures. Blood work showed that his thyroid levels were perfect. He was put on Phenobarb. The side effects of phenobarbital can include HUNGER and huge THIRST. Boy oh boy did Frasier get both, he was already a counter surfer but he would steal any food or drink, nothing like watching your dog slurp up your diet coke right out of the glass!
When he began taking the phenobarbital he was sluggish and he did have a bit of a glazed look, but that diminished after a few weeks. He did well on the phenobarb. When he passed, it wasn't from seizures or thyroid issues or complications there of. I miss my crazy boy.