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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.

From the WebMD Archives


Reality Bites

Wearing long sleeves and pants, never going barefoot, and avoiding insect-infested areas and nests will prevent most bites and stings. Spend enough time outdoors, though, and one day you'll likely feel that telltale pinch. How can you tell if a bite or sting is serious?

According to Pramod Kelkar, MD, an allergist and immunologist in Maple Grove, Minn., reactions to insect bites fall into three categories:

1. Normal Reaction

When insects bite or sting, they commonly inject a small amount of venom or chemicals under the skin. This irritating beetle juice causes the reaction most of us are familiar with:

  • A small area (less than half an inch) of redness, swelling, and itching
  • Pain, especially when stinging insects are involved.

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

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.