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Serious Allergic Reactions (Anaphylaxis)


What Is Anaphylaxis?

Anaphylaxis is a severe allergic reaction. Things that can cause allergic reactions are called allergens.

Anaphylaxis (an-eh-fil-AK-siss) most often happens during allergic reactions to:

Anaphylaxis can be scary. But being prepared will help you treat a reaction quickly.

What Are the Signs & Symptoms of Anaphylaxis?

Allergic reactions can cause:

  • trouble breathing
  • throat tightness or feeling like the throat or airways are closing
  • hoarseness or trouble speaking
  • wheezing
  • nasal stuffiness or coughing
  • nausea, belly pain, vomiting, or diarrhea
  • trouble swallowing
  • fast heartbeat or pulse
  • skin itching, tingling, redness, or swelling
  • hives
  • a feeling like something bad is about to happen
  • pale skin
  • passing out

Anaphylaxis can cause different symptoms at different times. It's considered anaphylaxis if someone has:

  • any severe symptoms, such as trouble breathing, repeated vomiting, passing out, or throat tightness
    or
  • two or more mild symptoms, such as hives and vomiting or coughing and belly pain

The person needs treatment right away.

How Is Anaphylaxis Treated?

Someone with anaphylaxis needs help right away. The reaction can get worse very quickly. So doctors usually want people with allergies to carry injectable medicine called epinephrine. Epinephrine enters the bloodstream and works quickly against serious allergy symptoms.

Doctors prescribe epinephrine auto injectors. These should always be with the child with allergies, including at school, sports, jobs, and other activities. The auto injector is small and easy to use.

If the doctor prescribes epinephrine for your child, the doctor will show you how to use it. Two auto injectors should always be with your child in case one injector does not work or your child needs a second dose.

Your doctor also might instruct you to give your child antihistamines in certain cases. But always treat a serious reaction with epinephrine. Never use antihistamines instead of epinephrine in serious reactions.

Give an epinephrine injection to treat anaphylaxis right away, as described in
            the article.

What Should I Do If My Child Has a Serious Reaction?

Seconds count during anaphylaxis. If your child shows signs of a serious allergic reaction:

  1. Give the epinephrine auto-injector right away. If you are alone with your child, give this medicine first, then call 911. If someone is with you, have the person call 911 while you give the epinephrine.
  2. Lay your child down with legs raised while you wait for the ambulance.
  3. Go to the emergency room, even if symptoms improve after epinephrine. Your child must be under medical supervision for several hours. This is because a second wave of serious symptoms (called a biphasic reaction) often happens. Your child can get more treatment at the emergency room, if needed.

What Else Should I Know?

Serious allergies can be alarming. But you can help keep your child safe. Be sure to:

  • Help your child avoid allergens.
  • Always having two epinephrine auto injectors with your child.
  • Tell any caregivers, teachers, or coaches about your child's allergy and be sure they know what to do in an emergency.
  • Check that your child's auto injectors have not expired and don't get too hot or too cold.
  • Have your child wear a medical ID bracelet so others know to use the epinephrine in case of an emergency.
Reviewed by: Larissa Hirsch, MD
Date reviewed: November 2019