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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 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 give bacteria a way to get in and cause infection.

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Ragweed Pollen and Fall Allergies

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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 Laura J. Martin, MD on October 22, 2012

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