Fortiflora is made by Purina and contains animal digest which is not good for cats. Some cats like the taste of it if you are using it only as a topper but I prefer higher quality products as toppers like freeze dried chicken that you can make into a “dust” with a Magic Bullet.
If you are wanting a probiotic, I prefer the products from Renew Life. For my cats (and us), I use the
Ultimate Flora 15b CFU at a dose of 1/2 cal twice a day.
If you can please go back to your inbox (Upper right corner...click on “inbox”) to the message I sent you there yesterday and send me the info, I’ll do your spreadsheet today. We cannot give you the best dosing advice for him without it. The way the dose was taken up, it’s possible he’s overdosed but we can’t tell without the spreadsheet.
If the dose is correct, by chance, we can tell you if and when you might need to do the tests at MSU.
It’s also good that you read back through this thread to be sure you got all the suggestions.