What happens when you put cat flea medicine on a rabbit?

Applying cat flea medicine on a rabbit can be dangerous and potentially toxic. Many cat flea treatments contain ingredients like permethrin, which is safe for cats but highly toxic to rabbits and can lead to serious health issues, including seizures or death. It's crucial to use medications specifically formulated for rabbits or to consult a veterinarian for appropriate treatments. Always read labels carefully and seek professional advice before using any pet medication on a different species.