Anaphylaxis: A Life-Threatening Allergic Reaction

Women using Anaphylaxis injection

Anaphylaxis is a severe, potentially life-threatening allergic reaction that occurs rapidly, typically within minutes of exposure to an allergen. It can affect multiple body systems and may cause symptoms like difficulty breathing, a rapid drop in blood pressure, hives, swelling, and gastrointestinal issues. Anaphylaxis requires immediate medical intervention, often treated with an epinephrine injection (like an EpiPen), as it can lead to anaphylactic shock and be fatal if not promptly managed. Recognizing and treating it quickly is crucial for preventing serious outcomes.

Symptoms of anaphylaxis:

  1. Skin Reactions: Hives, itching, or flushed/pale skin.
  2. Swelling: Particularly of the face, lips, tongue, or throat, leading to difficulty swallowing or breathing.
  3. Respiratory Issues: Shortness of breath, wheezing, or tightness in the chest.
  4. Gastrointestinal Problems: Nausea, vomiting, or diarrhoea.
  5. Cardiovascular Symptoms: Rapid or weak pulse, drop in blood pressure, dizziness, or fainting.
  6. Other Symptoms: Anxiety, confusion, or a sense of impending doom.

Immediate treatment with epinephrine is critical if anaphylaxis is suspected.

What Are the Four Stages of Anaphylaxis?

  1. Exposure and Sensitization: Contact with an allergen (e.g., food, insect sting) triggers the immune system.
  2. Early Reaction: Symptoms like itching, hives, and swelling begin, usually within minutes.
  3. Progressive Symptoms: Escalating to breathing difficulties, low blood pressure, and gastrointestinal distress.
  4. Shock Stage: Severe drop in blood pressure, leading to anaphylactic shock. Immediate treatment is crucial at this stage.

Five Most Common Triggers for Anaphylaxis

  1. Foods: Peanuts, tree nuts, shellfish, dairy, and eggs are common triggers.
  2. Insect Stings: Bees, wasps, and other stinging insects can cause severe reactions.
  3. Medications: Antibiotics like penicillin, aspirin, and other drugs may induce anaphylaxis.
  4. Latex: Found in gloves, medical supplies, and certain everyday items.
  5. Exercise: Sometimes, exercise itself or exercise in combination with certain foods can cause anaphylaxis.

How Long Does Anaphylactic Shock Last?

Anaphylactic shock can last anywhere from a few minutes to several hours, depending on how quickly it's treated. Without prompt medical attention, anaphylaxis can be life-threatening. Epinephrine (administered via an auto-injector like an EpiPen) is the primary treatment and should be given immediately when symptoms appear.

Can You Sleep Through Anaphylaxis?

No, you should never try to "sleep through" anaphylaxis. Symptoms can worsen rapidly, leading to unconsciousness or shock. If any signs of anaphylaxis occur, seek emergency medical assistance right away and use an epinephrine injector if available.

Understanding and identifying the symptoms of anaphylaxis early can save lives. If you or a loved one is at risk, proper allergy testing and preventive care are essential.

At our clinic, we offer Alex2 Allergy Testing to help identify your specific triggers, providing you with the knowledge to manage and avoid severe reactions. Take control of your health today—schedule an allergy test and get the answers you need.

Click here to schedule your allergy test. 

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Dr Ibrahim Mutlib

Dr. Ibrahim Mutlib (BMBS, BMedSci) is an experienced GP with specialist interests in mental health, gastrointestinal health, and respiratory medicine. A clinical leader and published author, he is passionate about innovative, patient-centred care that supports both physical and emotional wellbeing.

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