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Timeline of an Anaphylactic Reaction

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  • A Dangerous Allergy Response

    A Dangerous Allergy Response

    An allergic reaction is your body’s response to a substance that it deems dangerous or potentially deadly. Spring allergies, for example, are a mild, common allergy often caused by pollens or grasses.

    A more deadly type of allergic response is possible, too. Anaphylaxis is a severe and sudden allergic reaction. It occurs within minutes of exposure to an allergen. If not treated appropriately, anaphylaxis can turn deadly very quickly. Click through this slideshow to learn more about how an anaphylaxis reaction occurs—and how you should treat it.

  • The Exposure

    The Exposure

    An allergen may be inhaled, swallowed, touched, or injected. Once an allergen is in your body, an allergic reaction may begin within seconds or minutes. Milder allergies may not cause noticeable symptoms for several hours.

    The most common allergens include foods, medications, insect stings, insect bites, plants, and chemicals. An allergist is a doctor who specializes in diagnosing and treating allergies. They can help determine your specific allergy issues.

  • The First Symptoms of an Allergy

    The First Symptoms of an Allergy

    An anaphylactic response begins quickly after you come into contact with the allergen. Your body releases a lot of chemicals that are intended to combat the allergen. These chemicals set off a chain reaction of symptoms. These initial symptoms include:

    • chest tightness or discomfort
    • difficulty breathing
    • cough
    • nausea or vomiting
    • diarrhea
    • abdominal pain
    • difficulty swallowing
    • skin redness
    • itchiness
    • slurred speech
    • mental confusion
  • The Most Severe Reactions

    The Most Severe Reactions

    Initial symptoms may quickly turn to more severe problems. If these symptoms go untreated, you may develop one or more of the following symptoms or conditions:

    • low blood pressure
    • weakness
    • unconsciousness
    • abnormal heart rhythm
    • rapid pulse
    • loss of oxygen
    • wheezing
    • blocked airway
    • hives
    • severe swelling of the eyes, face, or affected body part
    • shock
    • airway blockage
    • cardiac arrest
    • respiratory arrest
  • Stay Calm, Find Help

    Stay Calm, Find Help

    If you are experiencing an allergic reaction, it’s important to focus and remain calm. Fully explain to a responsible person what just happened, what you think the allergen is, and identify your symptoms. Anaphylaxis will quickly leave you disoriented and possibly struggling to breathe, so it’s important you communicate the difficulties you’re having as quickly as possible to someone who can help. If you are alone when the reaction occurs, call 911 immediately.

  • Be a Helping Hand

    Be a Helping Hand

    If you are helping someone who is experiencing an allergic reaction, it’s important to encourage them to stay calm. Anxiety can make symptoms worse. This can escalate the reaction and make it worse.

    Identify what caused the reaction if you can and remove it. Make sure the person has no further contact with the trigger.

    Monitor them for signs of a reaction. If they show signs of difficulty breathing or loss of circulation, seek emergency help. If you know that the person is severely allergic to the allergen, call 911.

  • Reach for the Epinephrine

    Reach for the Epinephrine

    Many people with diagnosed severe allergies will receive a prescription for an epinephrine autoinjector from their doctor. If you are carrying your autoinjector when you begin experiencing the reaction, give yourself an injection right away. If you’re too weak to give the injection, ask someone who is trained to administer it. 

    It’s important to keep in mind that this medicine is a timesaver, not a lifesaver. Even after one injection, you must seek emergency treatment. Call 911 as soon as you inject the epinephrine, or have someone drive you to a hospital immediately.

  • Always Go to the ER

    Always Go to the ER

    Anaphylaxis always requires a trip to the emergency room. If you do not receive the proper treatment, anaphylaxis can turn deadly in as little as 15 minutes. 

    The hospital staff will want to monitor you closely. They may give you another injection. In the case of severe reactions, one injection is sometimes not enough. In addition, healthcare professionals can provide other medications, such as antihistamines or corticosteroids. These medicines can help treat any additional symptoms, including itchiness or hives.

  • First Exposure vs. Multiple Exposures

    First Exposure vs. Multiple Exposures

    The first time you’re exposed to an allergen, you may only experience a mild reaction. Your symptoms will likely be less severe and will not escalate as quickly. However, multiple exposures may eventually lead to more severe reactions. Once your body has experienced an allergic reaction to an allergen, it becomes much more sensitive to that allergen. This means that even small exposures can potentially trigger severe reactions. Make an appointment with an allergist after your first reaction so you can be tested and receive proper medical guidance.

  • Create a Plan

    Create a Plan

    Together, you and your doctor can create an allergy response plan. This plan will come in handy as you learn to cope with your allergies and teach others in your life what to do in case of a reaction. Review this plan annually and make changes as necessary.

    The key to prevention is avoidance. Diagnosing your allergy is the most important step for preventing future reactions. If you know what causes the reaction, you can avoid it—and the life-threatening reaction—altogether.