Spider Bites (Black Widow and Brown Recluse) (cont.)

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Are spider bites dangerous?

Most spiders do not have mouth parts strong enough to penetrate human skin, and the majority of spiders found in the U.S. and are actually harmless. There are two notable exceptions, the black widow spider and the brown recluse spider, which are both dangerous to humans. Spider bites are fortunately uncommon. In many cases, presumed spider bites are actually due to another skin condition or an insect sting.

The black widow and brown recluse spiders are more common in the southern states of the U.S. They prefer warm, dry climates and undisturbed areas such as basements, closets, woodpiles, attics, or under sinks. The black widow spider is a small, black, shiny spider with a red hourglass marking on its belly. The brown recluse spider is sometimes termed a "violin spider." It is about an inch long and has a marking resembling a violin on the upper part of its back. Bites from both the black widow and brown recluse spiders are dangerous to humans and require prompt emergency medical care.

What should you do if you are bitten by a spider?

  • Wash the site of the spider bite well with soap and water.
  • Apply a cool compress or ice pack over the spider bite location.
  • Over-the-counter pain relievers may be used to relieve symptoms. (Remember, do not give aspirin to children; use acetaminophen or ibuprofen instead).
  • Call the doctor or seek emergency treatment if the victim is a young child, if you think the bite may have been from a black widow or brown recluse spider, if any signs of an allergic reaction occur, if the bite area becomes infected, or if the victim develops a rash or severe illness.
  • If possible, retrieve the spider and bring it with you to the health care practitioner so that it can be definitively identified.
  • A tetanus booster shot may be necessary, depending upon the date of the patient's last immunization.
Medically Reviewed by a Doctor on 1/8/2014

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Spider Bites - Black Widow Question: Have you or someone you know ever been bitten by a black widow spider? Describe the experience.