There is no set dosage - my vet said to scatter a pinch over their food. Now neither he nor I know the scientific measurement of a pinch. Take a 1/4 teaspoon and use about 1/2 of that. There is no danger nor downside you cannot over dose. With probiotic you can give too much and the active ingredients will overwhelm the natural flora. I'd give the probiotic no more than once every two days.