Chemical control may not always be as successful as desired because spiders are mobile and may migrate back into the area. Also, species that sit on the web may not pick up much residual pesticide. Because some spiders, such as the brown recluse, can be difficult to control, homeowners may wish to engage a professional pest control operator. First aid for spider bites Relieve local swelling and pain by applying an ice pack, ammonia or alcohol directly to the bite area. In case of severe reaction, consult a doctor immediately and, if possible, take along the spider for positive identification.
Specific antivenin is available to treat some widow spider bites.
Wettable powder formulations generally provide superior residual control on wood, concrete and brick surfaces. Residual pyrethroid dusts such as cyfluthrin or deltamethrin provide excellent control in inaccessible void areas. Brown recluse infestations are best treated with a combination of sanitation, residual sprays and dusts in appropriate areas. Aerosol fogs are generally ineffective for all but exposed stages of spiders, but may provide a useful supplement to residual sprays and dusts.