Thanks for the info tkandz. Sorry to hear about Kodi , i can understand the distress associated with the condition.
The last attack Demi had was very similar to the seizures you described, in that it would happen straight after getting up and she would lose control of her bladder. But I haven't noticed any diarrhoea and the blood test she had when she had her first VS (or whatever is happening) attack was normal. She was doing the retching thing on one occasion after eating, but that's only happened once over the last 3 weeks. I'll mention these things to the vet when I take her back next week for her next arthritis injection.