Mice don't like peppermint smell. I put out drink bottle caps with a cotton ball in them. A few drops of peppermint oil on the cotton ball. I put out a few dozen of the things all over the house. Under stuff. They do leave. Just keep a few drops on the cotton ball about every month. House smells good, no mice. And if pets get in it, it doesn't hurt them. Its got to be peppermint oil. Not extract. And nothing with sugar added. Just plain oil.