I am so sorry for your cat, and hope he gets through this.
As for Performatrin, I used to feed the dry to my cats, as I was told by Pet Value staff, that it was the best, I started noticing that my cats vomitted often, and one of my cats did die of liver failure (December 7, 2001), but I never linked it to the food !
I changed food, because of the vomitting, and because the colour of the food changed (to a more yellow colour) and when I looked at the ingredients I saw the first one listed was, Corn .
I am sure that when I started feeding this food years ago, that this was not the case.
I now feed Costco's brand (Kirkland) and have had no problems since.
I wish you and your sweet guy the best of luck
What is man without beasts? If all the beasts were gone, men would die from great loneliness of spirit. For whatever happens to the beasts, soon happens to man. All things are connected.
~~Chief Seattle (Duwamish tribe)~~