It's looking like he might be okay. We were able to take him home last night. The emergency vet said they've never seen a cat bounce back like he has. They can't find any underlying causes, so they think it must have been an acute episode. If only we knew what caused it.

We had friends staying with us a couple of weeks ago with their toddler, and they did cut up grapes for her to eat several times, which is one of the things on the list. So maybe she dropped one and it went under a piece of furniture and he just recently found it? It was even more unlikely that he'd been exposed to anything else on the list, so I don't know.

They had us bring him back today for a checkup to see how he's doing now that he's been off fluids for a day, and his numbers did go back up a bit, hopefully not too much. My partner is there with him now waiting for the vet to give him more details.