Sorry for the delay in responding Laurie. There are two internal parasites common in pets-coccidia and Giardia.
Giardia is usually treated with an antibiotic such as metronidazole combined with an antiparasitic drug such as fenbendazole. The treatment usually lasts between five to seven days. Always take your pet to the vet the minute you suspect an infection.
Has he been tested specifically for Giardia? They may have so ask first. He may have an allergy to his food. You may try a different food specifically for allergies. Plain pumpkin is a good fiber and most cats like it. TDKland, we recommend Goats’ milk for kittens. Cats are lactose intolerant and can’t digest cows milk. Goats’ milk is full of nutrients, probiotics and gentler on their tummies. This can also regulate the poop. You can find it in the dairy section or the concentrate in the baking aisle. Mix the concentrate 1:1 with water or pedylite.
I know you’re confused and scared but he’s still active and that’s an excellent sign.
Let’s us know how you and your boy are doing.
PG