All of my dogs (big and little) have been on Interceptor year round from the time I brought them home with no problems. I have witnessed first hand a dog suffering from hearworm (not mine) and there is no way I would even think of not using it.
I should add that I live in PA and have cold winters and I have seen a mosquito a time or two in the winter in the house so.....it's year round for us.
__________________ Jamie, Mom to Mayzie and Mozes |