Before I begin, Pearl (the dog in question) lives at my grandpa's. I hardly ever get to see her, so I have no idea if the episodes I'm about to describe have happened since. My grandpa is very old fashioned and would not tell me if they did. I usually have to force him and guilt him into taking her to the vet. But she is vaccinated and has all her needs provided to her, so please don't tell me I'm being a terrible owner. I did not purchase or adopt this dog, my grandpa did, she technically belongs to him, I only look after her wellbeing. So, a while back I visited Pearl. I took her out on a walk in the fields, and she was happy as any dog can be. She would vanish in and out of sight (as she does, it's a very safe area) and had a ton of energy. Then, I look behind me, and see her walking towards me, so I stop to let her catch up. That's when I noticed something was very wrong - she was wobbling from side to side, as if she was drunk. Then she started limping, first on one leg, then the other. She was shaking, drooling, and she vomited about 5 minutes later. She kept falling over, so I carried her home. I panicked, made sure she was comfortable and immediately called the vet. (It was a sunday, and most vets in poland are closed on sundays, so I had to do quite a bit of searching). Then, I went to get her, and found her wagging her tail, cheerful as can be, as if nothing ever happened. This episode lasted about 1-2 hours. I took her to the vet anyway to be on the safe side. The vet found nothing wrong with her, tested her stool and blood, and sent her home. he said it shouldn't happen again. It did. I came back to see her a month later (yes, this is how often I can see my dog. I live in dorms.) And I take her out on a walk, and the same thing happens. She vanishes for a bit, reappears, and once again, same symptoms. This time instead of panicking, I watched her a bit closer. Sure enough, she was fine within an hour or two. Tail wagging and everything. She is about 4-5 (she's a rescue so we don't know exactly) a small pup, spayed, completely mixbreed. I considered vestibular disease, but she does not have a head tilt when it happens, and it doesn't seem progressive in any way. I don't think poisoning has this sort of effect on dogs, though it could be a possibility. I thought she may be ingesting antifreeze, since both episodes happened in the winter, and it's never happened in the summer. But I'm not sure, since both times we were in different locations. Any ideas? I'm terrified it's going to happen again. Has anyone ever seen this in a dog before?