How do I get rid of ants permanently?

Pepper-based compounds can help deter ants, but it's still best to treat them at the nest. If you can find products that are piperonyl-based, which is basically a type of pepper, those can work as an irritant to the ant's exoskeleton. However, ants are very communicative, so if one or two ants come into contact with an irritating substance, they're going to use pheromones to mark off that area. Other ants who come to that area will just go around it. That's why the best approach is generally to remove their food and water sources and use a granular bait to treat the colony at the nest.