If the nest is outdoors, best is to pour in hot water and flood the nest, just as long as your cat is not near you. Hot water is non toxic.Different ants respond better to different types of poison. It would be why if your house is being invaded, then an exterminator might be the way to go.
One of termites biggest enemies is ants. But not all ants, there are specific ones that have wars with and attack termite colonies.Do ants eat termites?