Oh, poor Spencer!

I had a couple of thoughts when I read your post:

1- Denver city water recently had parasite issues (not giardia ... something else.) It depends on what the city's source is, and how much rain you've had lately.

2- What about hairballs? My Thelma, who has chronic hairball issues, throws up right after eating whenever she is "working" on expelling a hairball. Does Spencer throw up hairballs ... maybe not the first, but the second or third time he vomits?

Bless Spencer's little heart. I sure hope he's better soon!

Dianne