Pre-anaphylaxis symptoms: what to know and do

Anaphylaxis is a fast, severe allergic reaction that can affect more than one part of the body. Early changes may appear in the skin, mouth, throat, lungs, stomach, or circulation. Look for raised itchy patches, flushing, tingling, swelling of the lips or tongue, throat tightness, hoarse voice, cough, wheezing, or trouble breathing. Nausea, vomiting, cramping, or diarrhoea can occur. Pale or clammy skin, weakness, confusion, faintness, or sudden drowsiness may indicate that circulation is being affected.

Symptoms may begin soon after exposure to a trigger such as a food, medicine, insect sting, or latex, but the pattern differs between people. A person can have anaphylaxis without a skin rash, so breathing, throat, stomach, or circulation symptoms still need urgent attention. Symptoms can worsen quickly, even when the first sign seems mild.

Treat suspected anaphylaxis as an emergency. If the person has a prescribed adrenaline auto-injector, use it promptly according to its instructions and call emergency services. Tell the dispatcher that anaphylaxis is suspected. Have the person lie down with their legs raised if comfortable; someone who is struggling to breathe may sit with their legs extended. Do not let them stand or walk. If they are vomiting or unconscious but breathing, place them on their side and keep watching their breathing. Do not give food or drink to someone who is having difficulty swallowing.

Stay with the person and note the suspected trigger and the time symptoms began. If symptoms continue or return, follow emergency guidance about further treatment while waiting for help. Antihistamines do not replace emergency treatment when breathing or circulation is affected.

Call emergency services immediately for throat or tongue swelling, noisy or difficult breathing, wheezing, faintness, collapse, confusion, or rapidly worsening symptoms after a possible allergen exposure. Also seek immediate help when symptoms involve different body systems, such as hives together with vomiting or breathing difficulty. Do not wait to see whether the reaction settles and do not drive the affected person yourself if they are becoming unwell.

Even after symptoms improve, medical assessment is needed because symptoms can return. After recovery, arrange follow-up to identify possible triggers, review the emergency plan, and discuss whether allergy testing is appropriate.

Ask what might have triggered the reaction, which symptoms should prompt immediate adrenaline, how to use an auto-injector, and how family, school, or coworkers should respond. Ask whether you need an allergy action plan, follow-up with an allergy specialist, or testing after the event. Share any medicines you take and describe the timing of every symptom.