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Allergies Health Center

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What Causes Allergies?

Almost anything can trigger allergies.

Some foods, vaccines, medications, latex rubber, aspirin, shellfish, dust, pollen, mold, animal dander, and poison ivy are common things people are allergic to.

Bee stings, fire ant stings, penicillin, and peanuts are known for causing dramatic reactions that can be life-threatening for some people.

Minor injuries, hot or cold temperatures, exercise, or even emotions may trigger allergy symptoms, even though you’re not allergic to these things.

Your allergic reactions are unique to you. For example, your body may have learned to be allergic to poison ivy from repeated exposure.

Allergies run in some families, although you can have allergies even if your parents don’t. Many people who are allergic to one thing are allergic to other things, too.

You’re more likely to have allergies if you’ve had:

  • A severe allergic reaction in the past
  • Lung conditions that affect breathing, such as asthma and chronic obstructive pulmonary disease (COPD)
  • Nasal polyps
  • Frequent sinus, ear, or respiratory infections
  • Sensitive skin

WebMD Medical Reference

Reviewed by Hansa D. Bhargava, MD on November 05, 2012

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