Allergy testing when you have asthma

A clinician interprets a skin-prick or specific blood test alongside the person's symptoms and exposure history. A positive result shows that the immune system recognises that allergen; it only becomes clinically useful when exposure is linked to relevant breathing or nasal symptoms.

Skin-prick testing places small amounts of selected allergens on the skin and checks for a local reaction. A specific IgE blood test looks for antibodies to selected allergens. Neither result measures how severe a future asthma flare will be, and neither identifies irritants such as smoke or strong odours as allergies.

Testing is most informative when the panel is chosen from a detailed history. Broad testing without a suspected exposure can uncover sensitisation that causes no symptoms and may lead to unnecessary avoidance.

Before the appointment, note where and when breathing symptoms occur, including contact with animals, dust, mould, pollen or workplace materials. Bring a medicine list. Some antihistamines interfere with skin reactions, so follow the testing service's specific instructions rather than stopping prescribed medicine independently.

Afterward, ask which findings match your real-world pattern. Targeted exposure reduction may complement asthma treatment, but do not make major housing, pet or dietary changes from a test report alone. Continue prescribed asthma medicines unless the treating clinician changes them.

Allergy testing is not the priority during an asthma attack. Seek emergency help for severe or rapidly worsening breathlessness, blue or grey lips, faintness, confusion, difficulty speaking, or poor response to the prescribed reliever. Follow the asthma action plan while help is arranged.

Tell testing staff before the procedure if asthma symptoms are currently worse than usual. Contact the clinic urgently if widespread hives, swelling, vomiting, dizziness or breathing difficulty develops after leaving a test appointment.

Ask which allergens fit your exposure history, whether skin or blood testing is more suitable, how medicines affect preparation and how each result would change management. Clarify whether separate breathing tests are needed to assess asthma itself.