Anaphylaxis is a severe and potentially life-threatening allergic reaction. The most common anaphylactic reactions are to foods, insect bites, medications, and latex. Symptoms of anaphylaxis come on suddenly and can include hives, swelling of the tongue, face, or throat, difficulty breathing, and an irregular heartbeat. If the reaction progresses to anaphylactic shock, it can be fatal. Anaphylaxis is a medical emergency that requires immediate treatment with an epinephrine auto-injector (EpiPen).

    Frequently Asked Questions

    • What does anaphylaxis mean?

      Anaphylaxis is a severe, sudden allergic reaction to an allergen such as a food, insect bite, medication, or latex. Symptoms include wheezing, vomiting, and hives. Anaphylaxis is a medical emergency that can lead to anaphylactic shock, which can be fatal.

    • How long does anaphylaxis last?

      Anaphylaxis symptoms generally start within minutes after exposure to the allergen, usually peaking within five to 30 minutes. In some cases, symptoms don’t occur for a few hours; rarely, they last for several days.

    • How is anaphylaxis treated?

      Anaphylaxis is a medical emergency. An injection of epinephrine (adrenaline) is frequently used for treatment, and can be self-administered with an auto-injector, such as an EpiPen.  Other medications, such as antihistamines (Benadryl) and steroids (prednisone), may also be used. A single injection from an autoinjector may not be enough to stop severe symptoms, in which case a repeat dose is required.

    • What happens after an anaphylactic reaction?

      If you don’t know what triggered the reaction, an allergist can perform tests to help identify the allergen. Going forward, the most important thing to do is to avoid contact with the allergen and always carry an EpiPen in case of a reaction.

    • What causes anaphylaxis?

      Anaphylaxis results when the immune system essentially “overreacts” to an allergen, causing an inflammatory response throughout the body. The most common triggers are foods, insect stings, medications, or latex.

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