I used to use dog FL+ on my cats when I lived where they could safely go outside. Haven't needed to do it the last two summers, thank goodness. I hate to put chemicals of any kind on an animal unless it's absolutely essential.

As I recall, one "large dog" dose of FL+ would treat 8 cats. I had seven, and what I did was put a bit more on the bigger cats and less on the smaller ones, to use up the whole ampule each time, because it's hard to store leftovers.