Overview
Anaphylaxis is a serious whole-body allergic reaction. It can happen very fast after exposure to a trigger and may block breathing, cause a dangerous drop in blood pressure, or lead to collapse. Quick recognition and emergency care are critical.
Key Symptoms
Symptoms often involve more than one body system at the same time. They can include trouble breathing, wheezing, throat tightness, swelling of the lips or tongue, hives, flushing, vomiting, diarrhea, dizziness, fainting, or a feeling of doom. Some people may first notice itching, rash, or sudden stomach symptoms before more severe signs appear.
Causes and Risk Factors
Common triggers include certain foods such as peanuts, tree nuts, milk, eggs, shellfish, fish, wheat, and sesame; insect stings; medicines; and latex. Exercise or alcohol can sometimes make reactions more likely or more severe in some people. Risk may be higher in people with asthma, previous anaphylaxis, or known allergies.
Who Is Affected
Anaphylaxis can happen at any age, including in children and adults. People with food allergies, insect venom allergies, medicine allergies, or latex allergy are at higher risk. A severe reaction can also happen in someone who did not realize they were allergic.
Prevention
Prevention focuses on avoiding known triggers and reading labels carefully. People with a history of severe allergic reactions should have an emergency action plan and know how to get urgent help quickly. Wearing medical identification and informing schools, workplaces, restaurants, and caregivers about serious allergies can also help.
Diagnosis and Tests
Doctors usually diagnose anaphylaxis based on the sudden pattern of symptoms and possible exposure to an allergen. Testing after recovery may help identify the trigger, such as allergy-focused history, skin testing, or blood tests ordered by a qualified clinician. Because symptoms can come and go quickly, the history of what happened is very important.
Treatment Categories
Emergency treatment is needed right away. Epinephrine is a standard first-line treatment used in emergency care for anaphylaxis, and people at risk may be prescribed an auto-injector by their clinician. Additional hospital treatment may include oxygen, breathing support, fluids, and monitoring because symptoms can return after first improvement.
Living With It
Living with a risk of anaphylaxis often means learning triggers, planning ahead, and teaching family or caregivers what to do in an emergency. Follow-up with an allergy specialist may help clarify causes and reduce future risk. Emotional stress and fear of another reaction are common and worth discussing with a healthcare professional.
When It May Be an Emergency
Anaphylaxis is always a medical emergency. Seek emergency help immediately if there is trouble breathing, throat swelling, fainting, severe weakness, widespread hives with vomiting, or rapid worsening after contact with a possible trigger. Do not wait to see if symptoms improve on their own.