★★★★★
We initially returned to the vet for a remedy/diagnosis (as the diarrhea had blood in it and was mucus-sy) and the vet gave us some harsh chemically smelling concoction.
My cat refused the concoction for his diarrhea and was very stressed when my husband and I tried to administer it. After a day or 2 it occurred to me to try some bentonite clay. I mixed up a solution (a flat tablespoon in a jar of water, leave to absorb, without mixing for at least 20 minutes, then mix)) and offered the cat some of the thicker part of the mix. He licked it all up without hesitation, I offered him more and he took the second dose. This was in the evening. The next day he did a nice healthy poo and was back to his normal self.
Please look into bentonite, green clay and edible clays generally. Thay are SO good for health (human and animal)
Good luck