Hi, It's a little unusual for rabbits to havefleas. Are you sure they have them? A few years ago we had a fleaproblem with the dog and cats (had to do with the weather....hothumid). To ensure that the rabbits didn't pick any up, I used the Hartz(squeeze tubes) for cats, on them. Half a dose that was recommended forcats, placed at the base of the head. You may have to Bomb your house,once a month, for 3 months in a row to get rid of your fleas.