What Is Allergic Asthma?

Allergic asthma is a type of asthma that is triggered by allergens, things that cause an allergic reaction [1]. When someone with allergic asthma breathes in an allergen, their immune system overreacts, leading to inflammation in the airways. This makes it harder to breathe and can cause asthma symptoms to appear or worsen.

What causes allergic asthma?

Allergic asthma is caused by the body reacting to allergens, which are usually harmless to most people. Common triggers include:

Pollen (from trees, grass, or weeds)
Dust mites
Pet fur or dander
Mould spores
Cockroach droppings (more common in some environments)

When you inhale one of these allergens, your body releases chemicals like histamine, which cause swelling and narrowing of the airways.

What are the symptoms of allergic asthma?

Symptoms of allergic asthma are similar to other types of asthma and may include:

Wheezing – a whistling sound when breathing
Shortness of breath
Coughing, especially at night or early morning
Chest tightness or discomfort
Runny nose, sneezing, or itchy eyes (typical allergy symptoms)

How is allergic asthma diagnosed?

Your GP or asthma nurse may recommend:

Reviewing your symptoms and medical history
Spirometry or peak flow tests to check your lung function
Allergy testing (such as skin prick or blood tests)

These tests help identify your asthma and confirm if allergens are a trigger [2].

How is allergic asthma treated?

Treatment aims to control both asthma symptoms and allergic reactions. This may include:

Preventer inhalers – taken daily to reduce airway inflammation
Reliever inhalers – used when symptoms appear
Antihistamines or nasal sprays – to manage allergy symptoms
Allergen avoidance – taking steps to reduce exposure at home or outdoors
Allergy immunotherapy – in some cases, to help the body build tolerance

Can allergic asthma be prevented?

There’s no cure, but symptoms can often be managed well. To help prevent flare-ups:

Keep your home clean and dust-free
Use allergy-proof bedding and wash it often
Keep pets out of bedrooms and off furniture
Stay indoors during high pollen counts
Take all asthma and allergy medications as prescribed [3]

Who is at risk of allergic asthma?

Allergic asthma is more common in people who have:

A family history of asthma or allergies
Other allergic conditions, such as hay fever or eczema
Regular exposure to allergens, indoors or outdoors

Key Takeaways

Allergic asthma is a type of asthma triggered by allergens like pollen, dust mites, and pet fur.
Symptoms include wheezing, breathlessness, coughing, and typical allergy signs like sneezing or itchy eyes.
Treatment involves inhalers, allergy relief medicines, and avoiding triggers where possible.
Regular check-ups and a personalised asthma action plan can help manage allergic asthma effectively.
While it can’t be cured, allergic asthma can be controlled with the right support and daily care.

Reminder: If you think allergies are affecting your asthma, speak to your GP or asthma nurse. Identifying your triggers is the first step to breathing easier and staying well.

Sources

[1] Types of asthma - Asthma & Lung UK

[2] Chabra R, Gupta M. Allergic and Environmentally Induced Asthma. [Updated 2023 Aug 7]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK526018/

[3] Akar-Ghibril N, Casale T, Custovic A, Phipatanakul W. Allergic Endotypes and Phenotypes of Asthma. J Allergy Clin Immunol Pract. 2020 Feb;8(2):429-440. doi: 10.1016/j.jaip.2019.11.008. Erratum in: J Allergy Clin Immunol Pract. 2020 May;8(5):1779. doi: 10.1016/j.jaip.2020.02.026. PMID: 32037107; PMCID: PMC7569362.