I had started this Catego this pass week. So far its working on her. She is not having any bad scratching at all so far. She is much better now then a week ago. My cat is 16pounds us highly Allergic to fleas. This is the 1st time I'm actually seen her not scratching yourself. She is a indoor cat. We will see how it goes for the next two months on this. But so far all is great.