What should you know about mild anaphylaxis symptoms?

Anaphylaxis is a serious whole-body allergic reaction. Early features may include sudden hives, flushing, itching, swelling of the lips or tongue, throat tightness, abdominal pain, vomiting, dizziness or a change in breathing. Skin changes may be absent, so do not wait for a rash before taking breathing or circulation symptoms seriously. Food allergy is one possible trigger, alongside medicines, insect stings and other exposures. [Wheezing](/symptoms/wheezing/) after a suspected allergen is an emergency warning sign.

If anaphylaxis is possible, use the person’s prescribed adrenaline auto-injector immediately and call emergency services. Follow the device instructions, keep the person lying down with legs raised if comfortable, or allow a person with breathing difficulty to sit with legs extended. Do not let them stand or walk. A second device may be needed if symptoms do not improve, following local emergency advice. Do not rely on antihistamines to treat airway or circulation problems. Read about [Anaphylaxis Emergency Treatment](/treatments/acute-and-urgent-care/anaphylaxis-emergency-treatment/) for the emergency approach.

Call emergency services for throat or tongue swelling, hoarse voice, trouble breathing, faintness, collapse, repeated vomiting, or symptoms involving more than one body system after a possible allergen. Symptoms can return after seeming to improve, so medical observation is needed. Anyone with a suspected first reaction should receive prompt clinical assessment; later [Allergy Testing](/treatments/diagnostics-and-screening/allergy-testing/) may help identify a trigger.

What triggers should I avoid? Should I carry an adrenaline auto-injector? Can you show me how to use it, and what is my emergency action plan?