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ACAAI > Patients & Public > Allergies > Anaphylaxis

Anaphylaxis Overview

Anaphylaxis is a rare but severe allergic reaction. It occurs suddenly, can worsen quickly and can be deadly. Anaphylaxis happens after being exposed to a triggering agent. The agent leads to the release of normal body chemicals such as histamine that cause allergy symptoms. The first-line treatment for anaphylaxis is epinephrine (adrenaline).

How can I pinpoint my anaphylactic trigger?

Any substance or food you had contact with just before the start of the anaphylaxis attack is a possible trigger. Make a very detailed list, and take this list with you when you see your doctor. Many times an allergist can help you find the trigger of your anaphylaxis attack. Testing may include skin and/or blood tests.

Food is the most common trigger for anaphylaxis. Severe allergic reactions to foods such as peanuts, tree nuts (walnuts, pecans, almonds and cashews), fish, shellfish, cow’s milk and eggs account for about half of all anaphylaxis cases and 100 U.S. deaths each year.

Stings from insects such as bees, wasps, hornets, yellow jackets and fire ants are the cause of about 500,000 allergy-related emergency room visits each year and at least 40 U.S. deaths from anaphylaxis.

Medications also can cause anaphylaxis, especially penicillin. Other commonly used medications that can trigger anaphylaxis include aspirin, anesthetics, antibiotics and pain relievers like ibuprofen.

Latex can trigger an allergic reaction in up to 6 percent of Americans, a number that’s increased in recent years because of more common use of latex in medical products like disposable gloves, syringes, stethoscopes and adhesive tapes. Health care workers, other workers who typically wear gloves and children with spina bifida are at greatest risk of latex-induced anaphylaxis.

What is idiopathic anaphylaxis ?

Sometimes, doctors cannot pinpoint the cause of your attack. When a specific trigger cannot be found, the trouble is said to be "idiopathic," which means "without known cause."

What should I do if I had an anaphylaxis attack in the past?

If you had an anaphylaxis attack in the past:

  • Wear a medical bracelet that lists your trigger.
  • Avoid your trigger. The most effective way to prevent future trouble is to avoid contact with your trigger.
  • Know what to do if you unexpectedly come into contact with your trigger. Your doctor can help you make a detailed plan for emergency care.
  • If your doctor has prescribed an epinephrine shot, carry it with you at all times.
  • Teach your family and friends how to help you if you begin to have anaphylaxis and cannot help yourself.

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