Was wondering if anyone here uses heartgard on their cats, I got free samples from my vet when I took my kittens in. We do live in a area of the country that has a mosquito problem. They are inside cats. I do give it to my dogs, but just in the past few months I've had a vet tell me to give it to my cats, they've never mentioned it in the past. I am planning on starting the younger ones on some kind of heart worm prevention. My vet says the older ones probably shouldnt take it. I know there are other brands and was wondering if anyone was using this one or any others on their cats?