What Is Allergic Asthma?

Allergic asthma is a type of asthma in which exposure to an allergen—an otherwise harmless substance such as pollen or dust mites—causes the immune system to mistake the allergen for a threat. In response, it overreacts by releasing chemicals that constrict the bronchi (airways) and triggering wheezing, coughing, and other classic asthma symptoms. Once diagnosed, allergic asthma typically is treated with a combination of practical measures, such as avoiding triggers, and medications to prevent asthma attacks and treat symptoms when they occur.

Also known as extrinsic asthma, this is the most common type of asthma, affecting about 60% of the 25 million people diagnosed with the disease.

Allergic Asthma Symptoms

Asthma causes inflammation of the bronchi and bronchioles, the airways that provide a path for inhaled air into the lungs. The subsequent narrowing of these passages results in the common symptoms of asthma, which include:

• Wheezing
• Coughing
• Chest tightness
• Shortness of breath

Because it can be triggered by the same allergens that cause allergic rhinitis (hay fever), people with allergic asthma also may experience typical seasonal allergy symptoms, including nasal congestion, runny nose, post-nasal drip, throat irritation, sneezing, itching, and red or watery eyes.

Causes

Although not fuly understood, allergic asthma is thought to be caused by a combination of inherited factors and environmental conditions.

If you have a family member with allergic asthma, you are more likely to develop the condition yourself. More than 100 genes have been identified as related to allergic asthma; some are associated with the immune system and others to lung and airway function.

Having a genetic inclination towards allergic asthma doesn't guarantee you'll develop the condition. Instead, it's believed that genes plus exposure to irritants, pollutants, and/or allergens leads to the onset of asthma.

Studies suggest certain environmental factors seem to initiate a change in gene activity in people who have inherited a predisposition towards allergic asthma.

Triggers

Common triggers of allergic asthma include:

• Pollen
• Dust mites
• Animal dander
• Mold

Once the allergen is in your system, it triggers your immune system. Your body then produces immunoglobulin E (IgE) antibodies, which release chemicals like histamine.

This initiates a cascade of responses that are responsible for symptoms and that can progress to a full-blown asthma attack:

• Tightening of the muscles around the bronchi and bronchioles
• Narrowing of the airways (bronchoconstriction)
• Swelling of the airways
• Overproduction of mucus

Over time, repeated asthmatic attacks can lead to airway remodeling, which is permanent narrowing of the bronchial tubes.

Diagnosis

To determine whether your asthma is related to an allergy, your doctor will first conduct a physical exam and medical history.

You will be asked about the conditions that seem to bring on your asthma symptoms. For instance, do you experience coughing, wheezing, and other symptoms during pollen season or when you dust?

Your doctor will then run specific allergy tests to identify whether you have a sensitivity to an allergen.

• Skin tests: Tiny samples of common allergens are placed on or just beneath the top layer of your skin to see if you have a reaction.
• Blood tests: Blood samples are tested to see if allergen exposure causes elevated levels of IgE.

As the different types of asthma can present with the same classic symptoms, confirming that your case is indeed due to an allergic response can help clarify exactly what is prompting your breathing difficulties—and what can be done about it.

Treatment

Allergic asthma can sometimes disrupt your everyday life and even lead to complications, but you can learn to manage exposure to allergens and treat symptoms effectively.

Three key components comprise allergic asthma treatment:

• Avoiding triggers
• Preventing asthma symptoms with maintenance medication
• Managing attacks with rescue medication

Avoiding Triggers

By closely monitoring your asthma, you can identify allergens that trigger symptoms. The best course you can take is to avoid these triggers whenever possible.

For example, this might involve staying indoors and keeping windows closed when pollen counts are high, if you are triggered by pollen. If you are allergic to an indoor allergen, recommendations for asthma management issued by the National Institutes of Health (NIH) in December 2020 include specific guidelines for dealing with certain ones:

Rodents, cockroaches, and other pests: Use integrated pest management—an environmentally-sensitive approach based on understanding the life cycles and other factors of a insect or animal in order to eliminate and control them—alone or in tandem with other mitigation measures.

Dust mites, cat dander, and other allergens: Take a multicomponent approach to mitigating allergens rather than rely on a single measure. For example, while the NIH approves using pillow and mattress covers to help control dust mites, this measure alone is not enough and should be shored up with others, such as using a vacuum cleaner with a HEPA filter, installing an air purifier system, and removing carpets.

Maintenance Medication

Both allergy and asthma treatments that prevent symptoms are commonly used to manage allergic asthma.

For allergies, your doctor may recommend antihistamines. These drugs are not considered a direct treatment for asthma. However, they can help you control allergy symptoms, which may reduce asthma flare-ups.

You may also be able to undergo immunotherapy (allergy shots) to reduce your sensitivity to allergens, an approach the NIH approves for children 5 and older and adults whose asthma is controlled during the several shots it takes to fully build immunity.

Long-term controller medications, sometimes taken daily, can be used to prevent asthma symptoms. Examples include:

• Inhaled corticosteroids  
• Inhaled long-acting beta-agonists (LABAs)
• Combination inhaled medicines 
• Biologics 
• Leukotriene modifiers
• Cromolyn sodium
• Theophylline 
• Oral corticosteroids 

Rescue Medication

Quick-relief medicines are used to treat asthma symptoms that arise despite efforts to prevent attacks. These treatments help relieve breathing problems when they occur, allowing airways that are constricted to open up so you can breathe fully. They include:

• Short-acting beta-agonists (SABAs) 
• Anticholinergics 

Combination quick-relief medicines may also be available. These include both an anticholinergic and a SABA with the medication delivered via inhaler or nebulizer.

A Word From Verywell

Allergies and asthma combine to create a challenging situation. One of the keys to managing your allergic asthma is being sure that all your doctors are aware of your medications and that you work together to form an asthma action plan that includes insight from an allergist, asthma specialist, and any other doctors you see regularly.