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Allergies Health Center

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Mosquito Bites

A mild allergic reaction to a mosquito’s saliva causes a small itchy welt that usually gets better within a few hours. But if you are highly sensitive, symptoms can last for several days. The small welt can develop into an itchy sore the size of a quarter.

It’s tough advice, but the best thing you can do is not scratch the bite. Scratching can create an opening in your skin that can allow bacteria in and cause infection.

Recommended Related to Allergies

Allergy Tips for Outdoor Living

Try these tips to enjoy outdoor living, gardening, and hiking despite your allergies. Thick of It: Is the grass getting high? Wear a mask if you're mowing. Nothing fancy -- an inexpensive painter's mask works fine. High and Dry: Pollen counts are highest on hot, dry, windy days. Check the forecast before making plans. Good Scents, Bad Sense: Allergic to insect stings? Don't wear scented deodorants, perfumes, shampoos, or hair products. Carry an epi pen when hiking. Orange...

Read the Allergy Tips for Outdoor Living article > >

To relieve itch and reduce risk of infection:

  • Wash the area with soap and water.
  • Apply calamine lotion or anti-itch cream.
  • Put an ice pack on the bite.
  • Take an over-the-counter antihistamine.

If a bite causes fever, vomiting, or shortness of breath, call 911 or get to an emergency room immediately.

To prevent future bites:

  • Stay indoors at dawn and dusk and in the early evening.
  • Wear long pants and long sleeves when you go outdoors.
  • Apply bug spray with DEET or picaridin to all exposed skin.
  • Get rid of standing water where mosquitoes breed.
  • Use screens on windows and doors to keep mosquitos out.

WebMD Medical Reference

Reviewed by Varnada Karriem-Norwood, MD on October 16, 2014

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