Anaphylaxis: Signs of a Severe Allergic Reaction and What to Do First

What it involves

MedlinePlus explains that anaphylaxis is a severe, whole-body allergic reaction to a substance that has become an allergen. After a first exposure sensitizes the immune system, a later exposure can release histamine and other chemicals that tighten the airways and cause other symptoms. It usually happens quickly after exposure, within seconds or minutes, and it can occur at any time.

Who this is for

• Adults who had a reaction with hives, swelling or trouble breathing and want follow-up after the emergency room.
• Patients with a known food, medicine or insect sting allergy who want to plan ahead.
• People who carry an epinephrine injector and need to review how and when to use it.
• Patients who had a milder allergic reaction and want to know if it could become severe.

What to expect

• A careful timeline of what you ate, took or were exposed to before the reaction
• A review of past allergic reactions and every medicine, since MedlinePlus lists some medicines as triggers
• A talk about avoiding triggers, carrying emergency medicine as directed, and wearing a medical ID
• A referral to an allergy specialist, who can test for the allergen, since tests are often done after treatment

Signs to recognize

MedlinePlus lists symptoms that develop quickly: hives, itching or redness of the skin, swelling of the face, eyes or tongue, difficulty breathing, coughing or wheezing, chest tightness, difficulty swallowing, dizziness, nausea or vomiting, abdominal pain, palpitations, slurred speech and loss of consciousness. A very hoarse or whispered voice can signal dangerous throat swelling. Several symptoms together, especially skin plus breathing trouble, make it an emergency. The hives guide describes milder reactions that stay on the skin.

Common triggers

MedlinePlus says anaphylaxis can occur in response to any allergen, and that common causes are medicine allergies, food allergies and insect stings. Pollen and other inhaled allergens rarely cause it, and some people have a reaction with no known cause. Some medicines can cause a similar reaction on first exposure, with the same symptoms and treatment. The food allergy guide, insect bites and stings guide and seasonal allergies guide explain how each type is evaluated.

What to do in the first minutes

MedlinePlus says to call 911 or the local emergency number, check the person's airway and breathing, and calm and reassure them. Use an epinephrine injector or intranasal epinephrine immediately if one is available, and do not assume earlier allergy shots give full protection. For a bee sting, scrape the stinger off with something firm rather than using tweezers. Have the person lie flat with feet raised about twelve inches unless they are vomiting, injured or uncomfortable. Do not put a pillow under the head or give food or drink.

After the emergency

People usually go to the emergency room first, and follow-up with a primary care provider helps connect the dots. MedlinePlus says tests for the allergen may be done after treatment if the cause is not obvious. A visit at Serenity By A Dr. Sareen can review the hospital records, your medicines and your history, and refer you to an allergy specialist. The practice does not list allergy shots among its services. The sick visit, urgent care or ER guide explains where each kind of care fits.

Prevention MedlinePlus recommends

To lower the risk, MedlinePlus advises avoiding triggers that caused a reaction before, asking detailed questions about ingredients when eating out, and reading labels carefully. People who have had serious allergic reactions should wear a medical ID tag or bracelet and carry injectable or inhaled epinephrine according to their provider's instructions. It says there is no contraindication to using epinephrine in a severe reaction. For children, new foods are introduced one at a time in small amounts so a reaction is easier to recognize.

What a primary care visit can add

Many people see several doctors and carry the same medicine list to each, and a primary care provider can keep it all in one chart. That helps when an allergy is linked to a prescription, and when a condition such as asthma makes any reaction harder to manage. The asthma guide explains why breathing conditions raise the stakes, and the hypertension management page is relevant if blood pressure medicines are part of your list. Bring your emergency room paperwork and any injector you were given.

Sources

• MedlinePlus: Anaphylaxis (health topic)
• MedlinePlus: Anaphylaxis (medical encyclopedia)