Asthma and anaphylaxis: what you need to know

Asthma mainly narrows the airways in the lungs, causing wheeze, cough, chest tightness or shortness of breath. Anaphylaxis is a rapid allergic reaction that can affect several body systems. It may cause throat or tongue swelling, a hoarse voice, widespread hives, vomiting, dizziness, collapse or sudden breathing trouble. Anaphylaxis can also trigger severe asthma symptoms, and asthma may make respiratory symptoms harder to manage during a reaction.

Breathing difficulty after a likely allergen exposure should not be assumed to be an ordinary asthma flare, especially when swelling, skin changes, faintness or stomach symptoms occur.

Use the prescribed adrenaline auto-injector without delay when anaphylaxis is suspected, then call local emergency services. Follow the device instructions and the person’s emergency plan. Keep the person lying down with legs raised if possible; if breathing is difficult, they may sit with legs extended. Do not let them stand or walk suddenly. If they become unresponsive and are not breathing normally, begin CPR if you know how.

A reliever inhaler may be used for wheezing according to the asthma plan, but it does not treat throat swelling, low blood pressure or the wider allergic reaction and must not delay adrenaline.

Seek emergency help for sudden breathing difficulty after food, medicine, an insect sting or another possible allergen; swelling of the tongue or throat; noisy breathing; a weak or faint feeling; confusion; collapse; or rapidly worsening symptoms. Emergency assessment is still needed if symptoms improve after adrenaline because they can return.

Ask how to distinguish your usual asthma pattern from an allergic emergency, when to use each medicine, how to check auto-injector expiry dates, and whether family, school or workplace contacts need training. Review inhaler technique and asthma control, discuss suspected triggers, and request written asthma and anaphylaxis action plans that work together.