Anaphylaxis is a severe, rapid-onset allergic reaction that can be life-threatening.
- It is a systemic reaction, meaning it affects the whole body.
- It occurs when the immune system releases large amounts of chemicals like histamine, causing sudden and widespread symptoms.
🔬 Explanation (How It Happens)
- Trigger exposure → Common triggers include certain foods (peanuts, shellfish), insect stings, medications (penicillin, NSAIDs), or latex.
- Immune overreaction → The immune system produces IgE antibodies that recognize the allergen.
- Massive histamine release → Mast cells and basophils release histamine and other chemicals.
- System-wide effects → Blood vessels dilate, airways constrict, fluid leaks into tissues → causing shock, swelling, and breathing difficulties.
📋 Signs & Symptoms
Usually begin within minutes of exposure (sometimes seconds):
- Skin: hives, itching, flushing, swelling (especially lips, face, tongue, throat).
- Respiratory: wheezing, shortness of breath, throat tightness.
- Cardiovascular: rapid heartbeat, drop in blood pressure, dizziness, fainting.
- Gastrointestinal: nausea, vomiting, abdominal pain.
- Severe cases: loss of consciousness, shock, cardiac arrest.
🩺 Emergency Treatment
- Epinephrine (adrenaline) → the first-line, life-saving treatment. Delivered by autoinjector (e.g., EpiPen).
- Call emergency medical services immediately.
- Supportive care: oxygen, IV fluids, antihistamines, corticosteroids (to prevent recurrence).
⚠️ Risk & Prevention
- People with known severe allergies should always carry an epinephrine autoinjector.
- Avoid known allergens and wear medical alert identification.
- Work with an allergist for testing and management.
👉 In short:
Anaphylaxis is a severe, whole-body allergic reaction that can be fatal without rapid treatment. Epinephrine is the critical first step, followed by emergency medical care.