Allergic asthma is the most common form of asthma. Many of the symptoms of allergic and nonallergic asthma are the same. However, inhalation of environmental allergens triggers allergic asthma.
Asthma is a breathing disorder in which a person’s airways become inflamed, causing recurrent episodes of breathing difficulty, called asthma attacks or exacerbations.
Environmental allergens may cause a person to have an allergic response anywhere in the respiratory tract. When allergens trigger asthma symptoms, doctors refer to this as allergic asthma. This condition affects around 60% of people with asthma.
This article looks at the relationship between asthma and allergies, which allergies or allergens can cause asthma, the differences and similarities between nonallergic and allergic asthma attacks, and the treatments for each.
We also look at other triggers and causes of asthma, how to manage allergies, diagnosis of allergic asthma, prevention, and the outlook for people with the condition.
A person with allergic asthma may experience symptoms after breathing in an allergen such as dust or pollen within the environment. Their immune system mistakenly identifies allergens as harmful. A complex reaction to these triggers in the body can cause the airways to inflame and swell, affecting a person’s ability to breathe and leading to asthma symptoms.
The most common symptoms of asthma are:
- coughing, especially at night, during exercise, or when laughing
- difficulty breathing
- chest tightness
- shortness of breath
These symptoms may become more severe if a person experiences exposure to a trigger, such as an allergen.
A severe attack can cause the airways to swell significantly, seriously affecting breathing. In this case, a person will require emergency medical treatment.
Although the symptoms of allergic and other types of asthma are mostly the same, the causes differ.
Triggers for allergic asthma differ from one person to another. Some allergens may cause more severe reactions in certain people compared with others.
Allergic asthma triggers
Common allergens that cause allergic asthma symptoms include:
- pollen, including from weeds, trees, and grasses
- pet dander
- mold spores
- dust mites
- cockroaches, including their body parts, feces, and saliva
Nonallergic asthma triggers
An asthma attack caused by nonallergic asthma presents in very similar ways to an allergic asthma attack.
As the name implies, factors other than allergens trigger nonallergic asthma. These can include:
Doctors may prescribe different treatments specifically for asthma or allergies. There are also some treatments for asthma and environmental allergies that overlap.
Treatments for asthma include:
- short-acting bronchodilators, which open airways quickly and immediately improve a person’s breathing
- long-acting bronchodilators, which keep airways open for longer periods than short-acting inhalers
- inhaled corticosteroids, which reduce inflammation in the airways
- biologics, a newer type of injectable medication that targets and modifies the immune system
Medication will not cure a person’s allergy but can help them manage the allergic reaction symptoms that can affect the whole respiratory tract. Allergy treatments are usually nasal.
A person should consult a doctor before using a medication to treat environmental allergies, even if it is available over the counter. Some of these medications include:
During immunotherapy, doctors expose a person to small amounts of an allergen via dissolvable tablets or injections. They gradually increase the amount of the allergen, which can desensitize a person to that allergen and reduce the chances of their immune system triggering an attack.
These medications relieve a blocked nose and can help ease breathing. A person will often inhale them as a nasal spray.
People may also find it beneficial to work with an allergist who can help them identify which allergens trigger their nasal allergies and asthma. The allergist can formulate a plan to assist the person in managing their symptoms and the allergens that affect them.
Leukotriene modifiers and corticosteroids are drugs that reduce swelling and inflammation in the airways for people with allergies or asthma.
A doctor will begin their diagnosis by asking the person about the symptoms they experience and noting anything that affects their severity.
They will then typically perform respiratory function tests to determine the effect of asthma on the person’s airways. These may include a fractional exhaled nitric oxide test to help determine how much lung inflammation is present by measuring nitric oxide levels in the airways.
They may also use spirometry, which involves the patient blowing into a sensor to measure the air their lungs can hold and the speed at which they inhale and exhale.
A doctor or allergist may also perform skin testing to identify reactions to specific allergens, using a plastic skin prick that contains a small amount of an allergen.
How do doctors determine if a person has allergic asthma?
The most definitive sign of allergic asthma that can help a doctor diagnose the condition is if a person experiences asthmatic symptoms after exposure to an allergen.
If factors other than allergens, such as exercise or respiratory infections, trigger a person’s symptoms, they may have a different type of asthma.
A person with allergic asthma should prioritize avoiding any known triggers to help control the condition. This may include:
- avoiding pets whose dander causes allergic reactions
- keeping dust to a minimum by regularly dusting their home with damp rags and washing clothes and other soft items regularly
- using allergen-proof bed coverings on mattresses and pillows to help keep dust mites off bedding
- vacuuming the home regularly to rid it of dust mites and cockroaches
- treating any sources of mold
- washing bedding regularly at a high water temperature to remove mites and other substances that may cause an allergic reaction
Asthma can be a long-term condition, although people may control and, in some cases, reverse asthma symptoms with treatment. In some people with long-term asthma, airways may narrow permanently and cause persistent problems breathing comfortably.
A person may need additional treatment for any conditions they have alongside allergic asthma, such as:
A person with asthma should always have access to an inhaler and seek emergency medical attention if they experience an asthma attack that does not immediately respond to home treatment.
Reactions to allergens in the immune system may cause asthma symptoms. Nonallergic asthma produces similar symptoms triggered by other factors such as exercise, stress, or extreme weather conditions.
A doctor can diagnose the condition by testing the person’s respiratory system and performing allergy tests, such as a skin prick test.
Common allergens that trigger asthma symptoms are dust mites, pet dander, and mold. A person may prevent attacks by avoiding allergens that trigger asthma. Treatment for allergies and resulting asthma can help reduce the severity of attacks. These treatments include medications such as inhalers, antihistamines, corticosteroids, and biologics.