Pronto Kill bed bugs and dust mites spraykill bedbugs and dust mites where they hide. To kill bedbugs apply as a spot treatment to cracks and crevices around baseboards, floorboards, headboards and walls. First thoroughly clean and air mattresses and springs. Then spot treat only areas that may harbor pests. On mattresses concentrate on tufts, folds and seams. Repeat as necessary. To kill dust mites first thoroughly vacuum entire room concentrating on areas where mites congregate: such as mattresses, box springs, headboards, walls, floors, carpeting, and baseboards. Then spray surfaces until damp. On mattresses allow spray to dry thoroughly before replacing bedding.