This time of year I usually apply permethrin to areas where fall home-invading insects in my area (cluster flies, box elder bugs, Asian lady beetles) congregate on my house. I also apply it under eaves, around windows and at other spots where they might gain entry. It seems to help keep them at bay in the home.

Permethrin acts as a broad-spectrum insecticide as well as a repellent, but is reasonably non-toxic to most mammals and birds. Farmers use it in the barn, and it's used in treatment for head lice. It is highly to toxic to cats and aquatic life, though.