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Allergic Reactions: What’s Normal, What’s Not

Allergies are common and usually not life-threatening. But there can be cases of anaphylaxis, a severe allergic reaction that needs immediate medical treatment.

You need to know the difference.

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Does your child miss school due to allergies? If so, you're not alone. Seasonal allergies are believed to affect as many as 40% of U.S. children. On any given day, about 10,000 of those children miss school because of their allergies. That's a total of more than 2 million lost school days every year. Even if your child doesn't miss school, allergies can get in the way of a productive school day, so managing allergies at school is an important part of caring for your child's health.

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In this article, you'll learn the symptoms of mild allergic reactions and an anaphylactic reaction. You'll also find out what to do if a child has anaphylaxis.

Allergy Symptoms: What's Normal

Kids with mild allergies (such as seasonal allergies) will usually have these symptoms:

  • Watery, runny eyes
  • Runny nose
  • Sneezing
  • Nasal congestion
  • An itchy rash or hives

These symptoms usually aren't serious. But stay on the lookout for more serious allergy symptoms (see below), especially in kids who have a history of asthma and severe allergic reactions.

Anaphylaxis Symptoms

Watch for these anaphylaxis symptoms and call 911 right away if you notice:

  • Difficulty breathing or noisy breathing
  • Hives
  • Swelling of the throat, face, lips, or tongue
  • Tightness in the lungs
  • Wheezing
  • Hoarseness
  • Pale or flushed skin
  • Sweating
  • Weak, rapid pulse
  • Low blood pressure
  • Dizziness, fainting
  • Nausea, vomiting
  • Abdominal pain

What Causes Anaphylaxis?

Many cases are caused by food allergies or insect stings.

In anaphylaxis, a child has a severe reaction to an allergy trigger.

Their airways narrow and their throat swells, which can block breathing. Their blood vessels widen, making their blood pressure fall, sometimes to dangerous levels.

Anaphylactic reactions usually happen fast. Symptoms often get the most severe within three to 30 minutes of exposure to the allergy trigger. Quicker reactions are usually more severe.

Be Prepared

A child who has had a severe allergic reaction should carry an emergency kit that includes an epinephrine auto-injector such as Auvi-Q or EpiPen.

You should know how to use the injector. So should your child's teacher. Your child may also be old enough to use it on themselves. Ask your child's doctor about that.

As soon as possible after the allergic reaction starts, give the child at least one shot of epinephrine. They may need more epinephrine injections.

The epinephrine injection is not a cure. It will not stop a severe allergic reaction. Even if the child seems OK, emergency medical care is a must.

Restock any items you used from the emergency kit so it's ready at all times. Check expiration dates on each epinephrine injection. Like all drugs, epinephrine has an expiration date.

WebMD Medical Reference

Reviewed by Arefa Cassoobhoy, MD, MPH on February 12, 2014

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