Flea medication's not gonna be harmful smashed up. Just less effective.
It basically puts toxins through the body that are harmless to the pet, but harmful/repelling to fleas. It lasts for X amount of time past the duration of the pill, so the quicker the pill gets absorbed, the less time it'll last. And it has to last a certain amount of time to drive all the fleas away/keep it lingering around so no more come.
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SEP Nash, Smelling Like the Vault since 1996
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