How To Treat a Black Widow Spider Bite

black widow spider - Latrodectus hesperus in web at night, desert wash habitat
••• Black Widow Spider. Marshal Hedin/Wikimedia Commons

If you are experiencing serious symptoms after being bitten by any insect including a black widow spider, seek medical attention immediately or call 9-1-1.

Black widow spiders are common in Phoenix, and in the Southwest U.S. in general. They hide in the dark recesses of garages, sheds, woodpiles. Here's what to do if you are bitten by a black widow spider.

About the Black Widow Spider Bite

  1. The black widow bite may feel like a pin prick, or it might not even be felt at all.
  1. You might notice two faint red spots surrounded by local redness at the bite. At first, there may be only slight local swelling.
  2. Pain usually progresses up or down the bitten arm or leg, finally localizing in the abdomen and back. There may be pain in the muscles and soles of the feet, and eyelids may become swollen.
  3. Widow spiders inject a toxin that affects the nervous system (neurotoxin). Muscle and chest pain or tightness are some of the most common reactions to the black widow toxin.
  4. Other symptoms may be nausea, profuse perspiration, tremors, labored breathing and speech, and vomiting.
  5. In more serious cases, a weak pulse, cold clammy skin, unconsciousness, or convulsions may occur.
  6. Only the bite of the female, usually the adult female, is potentially dangerous. Although extremely painful and temporarily debilitating, fatalities from untreated widow bites are uncommon.

Treating the Black Widow Spider Bite

  1. Remain calm. Collect the spider, if possible, for positive identification and get medical attention immediately.
  1. Clean the site well with soap and water. Apply a cool compress over the bite location to minimize swelling and keep the affected limb elevated to about heart level.
  2. Contact your physician, hospital and/or Poison Information Center. In Arizona we have a 24-hr toll free number for access to the Banner Poison Control Center. Call 1-800-222-1222.
  1. Application of a mild antiseptic such as iodine or hydrogen peroxide prevents infection. Try to keep the patient quiet and warm.
  2. The very old, very young, and those with a history of high blood pressure are at greatest risk. Prompt medical treatment can greatly reduce the danger.
  3. In severe cases, physicians can intravenously inject calcium gluconate to counteract most effects of the toxin. A black widow antiserum also is available.
  4. Don't try to suck out the poison. That doesn't work.