Read the label, as we have to do more and more now. Bring your magnifying glass. Know what is in it before you use it. The vet told me after a $250 visit (with an apoquel scrip) that some of his clients are having the same issue with the drops and to stick to ones they've used before that may not be the cheapest. You get what you pay for, and they're getting a lawsuit. User's recommendation: DON'T BUY.