My Simon is still throwing up everything. We took him back to the vet but he just gave him some prescription food which he is throwing up. GAAAA

He has lost around 6 pounds since March when we had him in there first. The vet said he is now at a good weight but I see bones and can feel his spine when I pet him. I'm not sure if 10 pounds is the right weight for a 7 year old cat.

Anyway, I think I am going have to diagnose him myself. Is there a site that gives some idea what is wrong if you put in the symptoms? Any good vet sites out there?