they have to be FREE of all additives such as sugar, salt, soy, gluten etc.....or if you can buy a good
brand of
yogurt, with multi strains of bacteria...a PLAIN, non flavored, with no additives...you can give him some of that each day and the problem will correct itself in no time...
these are human supplements that are safe for kitties, just remember the dosage recommended are for us, a little cat needs much less, I usually put just a sprinkle of the powder in their food.
http://www.iherb.