What to know after anaphylaxis

Anaphylaxis is a rapid, severe allergic reaction that can affect the skin, airways, breathing and circulation. Symptoms may include swelling of the lips or tongue, wheezing, difficulty breathing, widespread hives, faintness, vomiting or sudden collapse. Improvement after emergency treatment does not establish that the episode is fully over, so observation and clinical review are important.

The cause may be a food, medicine, insect sting or another trigger. A food allergy is one possible cause, but the trigger is not always obvious after the first episode. Follow-up helps clarify what happened and how to respond if exposure occurs again.

Follow the discharge plan, keep prescribed emergency medicine accessible, and make sure close contacts know how to use it and when to call emergency services. Record the suspected trigger, timing and symptoms. Avoid the suspected trigger until reviewed by a clinician; do not test it at home. Allergy testing may be arranged when appropriate, alongside advice about an emergency action plan and medical alert information.

Call emergency services immediately for wheezing, throat or tongue swelling, trouble breathing, faintness, collapse, widespread symptoms or rapidly returning symptoms. Use the prescribed emergency treatment as instructed while help is coming. A person with suspected anaphylaxis should not drive themselves or remain alone, even if they begin to feel better.

Ask what may have triggered the reaction, whether an allergy referral or testing is suitable, which emergency medicines to carry, and how family, school or workplace contacts should respond.