Spider bites are usually harmless. In fact, many bites attributed to spiders turn out to have been inflicted by other bugs. Skin infections also have been mistaken for spider bites.

Only a few types of spiders have fangs long enough to penetrate human skin and venom strong enough to severely affect a human being. In the U.S., these include the black widow spider and the brown recluse spider.

Black widow spider bites can cause severe abdominal pain and cramping, while brown recluse spider bites can cause the skin around the bite to die. Both these spiders generally live in undisturbed areas, such as attics or sheds, and don't bite unless threatened.

May. 21, 2013