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Coping With Bug Bites

Bug bites may seem like a rite of passage for enjoying the outdoors, but WebMD tells you how to protect yourself and when to take emergency action.

Reality Bites continued...

The worst of these symptoms should resolve within a few hours, and simple remedies can help ease the discomfort:

  • Over-the-counter pain medicines like ibuprofen (Advil or Motrin) or acetaminophen (Tylenol)
  • Cold compresses or ice
  • Calamine lotion for itching.

2. Large, Local Reactions

Rarely, the reaction gets worse instead of going away. A revved-up immune response to a bite or sting may lead to significant swelling and pain over a larger area of the body.

Large local reactions:

  • Can spread to involve an entire arm or leg
  • Can be severely painful and disabling
  • Often require treatment with a prescription medication, such as prednisone (an oral steroid), to fight inflammation.

Large local reactions develop slowly and usually require a trip to the family doctor, not the ER.

How do you know when it's time to get help?

  • After a few hours, the swelling is getting worse, not better
  • The swelling involves more than one-third of your arm or leg
  • Pain and swelling stop you from using that part of your body.

You can't predict if you'll get a large local reaction, but, "If you've had this reaction before, you are more likely to have it again," says Kelkar.

3. Life-Threatening Reactions (anaphylaxis)

This is the bad stuff. A small minority of people are at risk -- between 1 in 300 and 1 in 2000. Although rare, this reaction to common insect bites can be life-threatening. What is anaphylaxis?

  • An allergic reaction that spreads through the whole body
  • Itching and swelling that commonly occur far away from the bite or sting
  • Swelling that can squeeze the lung's airway closed -- a medical emergency.

What are the warning signs of anaphylaxis?

  • Itching all over your body. "Some people ignore the itching until they have difficulty breathing, which is a mistake," says Kelkar.
  • Having trouble breathing. According to Kelkar, some people won't have any itching, so this will be their first warning sign.
  • If these symptoms occur, call 911. Taking an antihistamine like Benadryl can slow the process, but urgent medical attention is essential.

How can you know if you're vulnerable to anaphylaxis? Unfortunately, you can't. But according to Kelkar, "If you've had a large local reaction, you're at slightly higher risk." Although a third of the people who get life-threatening reactions have other allergies, "the vast majority of people with allergies will never have a serious reaction to an insect bite," Kelkar points out.

Spiders and the Itsy Bitsy Bite

Most spiders are creepy, scary, and harmless -- their jaws can't even penetrate human skin. Spiders are not aggressive; in fact, they'll run any chance they get.

When spiders do bite (if surprised or trapped), they typically cause tiny wounds with minor reactions. But there are two spiders in North America that have a dangerous bite.

  • Black Widow. The female black widow is shiny, with a red hourglass marking on her belly's underside. If you think you've been bitten by a black widow spider, seek medical attention immediately. Although it is extremely poisonous, no one has died from a black widow bite in the U.S. in more than 10 years.
  • Brown Recluse. These shy spiders live only in the central and southern U.S. Their bite can cause a large, serious wound that needs medical attention. However, "The brown recluse often gets blamed for causing skin lesions in areas of North America where it doesn't exist," says Rick Vetter, an arachnologist with the University of California, Riverside.

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