Poisoning in cats is often hard to detect until it’s too late. Cats are predators, and all predators hide disease incredibly well. It's not in their favour. In evolutionary terms, if a predator looks sick, then other predators will turn on them. So cats tend to hide the symptoms of poisoning very well. But if you think keeping the cat inside to protect it, think again. Many of the poisoning dangers faced by cats are found inside the home.