You don't want to have them licking the spot(s) where you applied it, if you have to, put it on right before bed, and keep them seperated while they sleep until it's dry in the morning.

It is not ment for oral use.

Also, do NOT put Advantage on 3 days before, or 3 days after giving them a bath, or it will not work as well, or at all. Bathing strips the oils from their skin, and it's the oils the advantage works with to spread through out their body.