Anaphylaxis

Overview

Anaphylaxis is a severe, potentially life-threatening allergic reaction by the immune system to a substance. This intense reaction can affect the entire body within minutes, causing blood pressure to drop suddenly and airways to narrow. Without immediate intervention, anaphylactic shock and fatal outcomes can occur. Proper knowledge and an emergency action plan are lifesaving in such situations.

Your immune system normally works to keep out harmful substances. However, in anaphylaxis, it releases an excessive amount of chemicals in response to a substance that is actually harmless (such as food, medication, or insect venom). These chemicals create a storm in the body, causing blood vessels to widen and tissues to swell. As a result, blood flow is disrupted and breathing becomes difficult.

Anaphylaxis does not always stem from a substance you were previously known to be allergic to. Sometimes, the first exposure can be surprisingly severe. Most cases can be controlled with an adrenaline (epinephrine) injection and emergency medical support. The most important rule in treatment is to act without losing time as soon as symptoms begin.

Symptoms of anaphylaxis

Anaphylaxis symptoms usually start immediately after contact with an allergen, within seconds or minutes. Multiple systems of the body react at the same time. The speed and severity of symptoms can vary from person to person but generally tend to worsen rapidly.

• Skin reactions: Widespread itching, redness, or hives (welts) occur. The skin usually feels warm and moist.
• Swelling of the face and throat: The lips, tongue, or throat can swell quickly. This makes swallowing difficult and causes hoarseness.
• Breathing difficulty: Wheezing may be heard as airways narrow. A feeling of tightness in the chest and shortness of breath are prominent.
• Low blood pressure and dizziness: Blood pressure drops suddenly. This leads to weakness, lightheadedness, and a feeling of fainting.
• Gastrointestinal complaints: Severe abdominal pain, nausea, vomiting, or diarrhea may be seen.
• Rapid and weak pulse: The heart starts beating very fast to compensate for the dropping blood pressure, but the pulse feels weak under the hand.

When to seek emergency help

If you or someone with you experiences shortness of breath, throat swelling, or a feeling of fainting, call your local emergency number immediately. If the person has an "epinephrine auto-injector," use it right away without waiting for the ambulance. Do not be misled if symptoms ease; a second wave of reaction (biphasic reaction) can return a few hours later.

Causes of anaphylaxis

The causes of anaphylaxis include foods, medications, and insect stings as the most common triggers. The immune system perceives these substances as a major threat. The severity of the reaction can be very high, regardless of the amount exposed.

• Food allergies: Peanuts, tree nuts (walnuts, almonds), milk, eggs, fish, and shellfish are the most common triggers.
• Medications: Certain antibiotics, especially penicillin, painkillers, and contrast dyes used in imaging are common causes.
• Insect stings: Venom from bees, wasps, and some types of ants is a frequent cause of anaphylaxis.
• Latex: Natural rubber latex found in some medical gloves, balloons, or condoms can create a reaction in sensitive individuals.
• Exercise: Although rare, physical activity performed after eating a certain food can trigger anaphylaxis in some people.

Treatment of anaphylaxis

The first and most important step in treating anaphylaxis is the administration of adrenaline (epinephrine). Adrenaline raises blood pressure and quickly opens the airways to stop the reaction. In a hospital setting, additional supportive treatments are applied.

• Epinephrine auto-injector: People with known allergies carry this pen. This injection, applied to the thigh area, is lifesaving.
• Oxygen support: Oxygen is provided via a mask to relieve shortness of breath and ensure oxygen reaches the tissues.
• Intravenous fluids: Fluids are given through an IV to raise blood pressure and support circulation.
• Antihistamines and cortisone: These drugs help reduce skin reactions and prevent late-phase responses.

Prevention of anaphylaxis

The only way to prevent anaphylaxis is to completely avoid known triggers. Being prepared for those in high-risk groups prevents complications.

• Identify your triggers: Confirm which substances you are allergic to through testing.
• Read labels: Always check the ingredients in prepared foods.
• Carry your emergency kit: Keep your adrenaline pen with you at all times, everywhere.
• Inform others: Provide information about your allergy to school, workplace, and close circles. Use a medical alert bracelet if necessary.