Borax is a white crystalline powder that is used as a household cleaner, ant killer, and laundry booster. It is also effective in treating fleas and lice on pets. When mixed with sugar, borax makes an effective bait for killing ants. However, we don’t recommend that you use poisons to kill ants without professional guidance. If you’re using borax as an ant bait, be sure to put it in a place where children and pets can’t reach it. You should also avoid inhaling the powder or getting it in your eyes.