Different Types of Asthma: Which One Do You Have?

Different types of asthma include:

• Allergic asthma
• Non-allergic asthma
• Cough-variant asthma
• Nocturnal asthma
• Exercise-induced bronchoconstriction
  
• Occupational asthma
• Obese asthma
• Medication-induced asthma
• Viral-induced asthma
• Glucocorticoid-resistant asthma

They have similarities, but several also have unique characteristics that influence how they are triggered, diagnosed, and treated.

What Asthma Types Have in Common

Asthma has certain features that remain the same across most types:

• Classic symptoms: Wheezing, chest tightness, shortness of breath, cough, asthma attacks
• Causes/risk factors: Genetics and environmental exposures (like smoke)
• Diagnosis: Pulmonary function tests (PFTs) and assessing response to asthma medications
• Treatment: A rescue inhaler for asthma attacks and possibly daily inhaled or oral medications to prevent symptoms

Because of this, it's easy to assume that all types of asthma are fundamentally the same. While that's true to an extent, differences between the types matter—making an accurate diagnosis crucial.

Allergic Asthma

Allergies are involved in between 50% and 80% of asthma cases. People with seasonal allergies (hay fever) may also be diagnosed with seasonal allergic asthma.

Symptom Triggers

Common triggers of allergic asthma include:

• Pollen
• Mold
• Dust mites
• Animal dander

Additional Symptoms

Classic asthma symptoms are accompanied by allergy symptoms, such as:

• Nasal congestion
• Runny nose
• Scratchy throat
• Sneezing
• Itchy, red, and/or watery eyes

Causes and Risk Factors

Allergic asthma is believed to have a heavy genetic component plus hypersensitivity and exposure to the triggering substances.

Additional Diagnostic Tests

To confirm allergic asthma and determine triggers, allergy tests may also be ordered, like:

• Skin tests: Common allergens are put on your skin to see if you react to them
• Blood tests: Elevated levels of immunoglobulin E (IgE) antibodies, which your body produces in response to allergens, confirm an allergic reaction

Additional Treatments

You'll need to manage both asthma and allergies. That may include avoiding triggers, taking allergy medication (antihistamines), or allergy shots (immunotherapy).

Non-Allergic Asthma

Between 10% and 33% of all people with asthma have non-allergic asthma. It usually develops later in life than allergic asthma.

Some research suggests that non-allergic asthma is more severe than other forms. Studies also indicate it is more common in women.

Symptom Triggers

Non-allergic asthma symptoms can have a variety of triggers, including:

• Cold weather
• Humidity
• Stress
• Exercise
• Heartburn/acid reflux
• Pollution, smoke, or other irritants in the air
• Respiratory infections (e.g., cold, flu)
• Strong odors and sprays

Additional Symptoms

Non-allergic asthma isn't associated with additional symptoms.

Causes and Risk Factors

Things that may lead to non-allergic asthma include:

• Environmental tobacco smoke
• Viral infections
• Other medical conditions

Additional Diagnostic Tests

No test can specifically diagnose non-allergic asthma. Diagnosis can involve skin and blood tests to rule out allergies.

Additional Treatments

You may not need treatments beyond what's generally prescribed for asthma.

However, some people with non-allergic asthma don't respond well to inhaled corticosteroids (ICS). These drugs are used as daily preventive medication for moderate to severe asthma.

If ICS don't work for you, you may need other preventive drugs such as:

• Leukotriene modifiers
• Long-acting beta-agonists (LABAs)
• Long-acting muscarinic antagonists (LAMAs)

Cough-Variant Asthma

A dry cough is the main symptom of cough variant asthma (CVA). It may remain your sole symptom or go on to develop other symptoms, especially if not adequately treated.

Symptom Triggers

Because a dry cough doesn't usually make people think they have asthma, symptom triggers are an important part of figuring out you have the condition.

Watch for bouts of coughing that:

• Wake you up
• Come on after exercise
• Worsen in cold, dry weather
• Worsen with hay fever or other things allergic triggers

Additional Symptoms

CVA doesn't have additional symptoms.

Causes and Risk Factors

Cough-variant asthma may be an early symptom of emerging asthma; children have it more often than adults. Even so, about 30%-40% of people with CVA develop classic asthma.

Additional Diagnostic Tests

CVA is hard to diagnose. In addition to standard asthma tests, a sputum test may be ordered to look for white blood cells that are often increased with asthma. Sputum is a type of mucus coughed up from the lungs.

Additional Treatments

Treatment for cough-variant asthma is generally the same as for other types of asthma.

Nocturnal Asthma

Nocturnal asthma, as a diagnosis, is usually added to a pre-existing asthma diagnosis. If you have marked nighttime symptoms, you might have nocturnal asthma, or it could be that your asthma is not well controlled.

More than 50% of adults with asthma have nocturnal asthma. About 26% of children with asthma have this form as well.

Symptom Triggers

Nighttime symptoms of asthma may happen monthly, weekly, or even every night.

Environmental symptom triggers can include irritants present in the bedroom, like pet dander or dust, or sleeping with the window open.

Additional Symptoms

The symptoms of nocturnal asthma are the same as classic asthma symptoms. They just happen to be prominent at night.

Sleep interruptions from nocturnal asthma may happen several times per night and cause daytime tiredness. Many people fall back to sleep quickly and do not recall waking up.

Disrupted sleep from nocturnal asthma can increase the risk of serious complications, including heart disease, respiratory arrest, and asthma-associated death.

Causes and Risk Factors

Nocturnal asthma is believed to be caused by changes in the body that occur at night.

Circadian rhythm, your internal body clock, contributes to nocturnal asthma by causing nighttime shifts in:

• Muscle control
• Airway resistance
• Inflammation
• Hormones

Additionally, obstructive sleep apnea, a sleep disorder that interrupts breathing during sleep, is common among people who have asthma. And the conditions can exacerbate one another.

Additional Diagnostic Tests

Testing breathing during the day doesn't help diagnose nocturnal asthma. Thus, an at-home monitor may be necessary to test breathing close to bedtime.

Depending on symptoms a sleep study may also be advised. This typically involves spending the night at a sleep lab to have symptoms monitored. Some sleep studies can also be done at home with special equipment.

Treatment Changes

Nocturnal asthma is treated with the same medications as classic asthma but may require adjusting the timing of regular doses.

For example, rather than taking a daily control medication in the morning, you might take it in the afternoon or early evening.

Some researchers have suggested time-release tablets for treating this type of asthma. These dissolve slowly, so they remain effective over a long period.

Exercise-Induced Bronchoconstriction

Exercise-induced bronchoconstriction (EIB) used to be called exercise-induced asthma (EIA).

Up to 90% of people with any type of asthma may have exercise-related symptoms. However, many people with EIB don't fulfill the diagnostic criteria for asthma.

Symptom Triggers

In EIB, bronchial tubes (airways) narrow with exercise. It is believed that rapid breathing during exercise can dehydrate the bronchial tubes, which then constrict.

Typically, symptoms begin during exercise but can continue to worsen for 10 to 15 minutes after exercise is stopped.

Symptoms generally clear up without treatment within 30 minutes. However, it's safer to use a rescue inhaler than wait to see if symptoms will improve without it.

When combined with exercise, certain factors may make EIB more likely. They include:

• Cold weather or a cold environment (such as a skating rink)
• Hot air (such as during hot yoga)
• Chlorine in swimming pools
• Air pollution or other airborne irritants
• Recent respiratory infection or asthma attack
• High pollen count (especially if you also have allergic asthma)
• Odors such as perfume, paint, cleaners, and new carpet or exercise equipment

Low-intensity activities (e.g., walking, hiking) or sports with short bursts of exertion (e.g., baseball, wrestling, gymnastics) are less likely to trigger EIB.

Additional Symptoms

EIB can have a few symptoms not common in asthma, including:

• Decreased endurance
• Upset stomach
• Sore throat

Causes and Risk Factors

If you have asthma, minor irritation or dehydration from exercise may cause EIB. In this case, the cause of EIB is underlying asthma.

For people who don't have asthma, repeated exposure to cold, dry air, or airborne irritants while exercising may damage bronchial tubes and cause EIB.

This may explain why EIB is especially common in cold-related sports (like ice hockey and skiing) and among competitive swimmers (due to chlorine fumes).

People with environmental allergies or those with close relatives with environmental allergies have a higher risk of developing EIB.

Additional Diagnostic Tests

Regardless of whether there has been a diagnosis of asthma, breathing will be tested before and after exercise to determine EIB.

Forced expiratory volume (FEV1), which is a measure of how much air you can force out of your lungs, will also be tested before and after exercise. A decrease of 15% or more generally leads to a diagnosis of EIB.

Treatment

In people diagnosed with asthma, preventing bronchoconstriction will be part of an overall treatment plan.

EIB can sometimes be prevented by:

• Warming up for 10 to 15 minutes before vigorous exercise
• Covering the face with a mask or scarf while exercising
• Avoiding exercise in areas with high pollutant or allergen contents

A healthcare provider may recommend the following:

• A rescue inhaler or a long-acting inhaler before exercise to prevent attacks
• A rescue inhaler when an attack occurs

Occupational Asthma

Some jobs expose people to substances that can lead to occupational asthma (OA). This may account for about 15% of asthma cases in the U.S.

If other forms of asthma are present, these workplace exposures can make symptoms worse.

Symptom Triggers

More than 250 substances are believed to cause and trigger OA symptoms. Typically, symptoms are only triggered by the substance(s) you're in regular contact with.

Common triggers include:

• Animals
• Certain types of mold
• Cleaning products
• Chemicals including hydrochloric acid, sulfur dioxide, and ammonia
• Dust from wood, flour, or grains
• Insects
• Latex
• Paints

Many other potential triggers exist.

Additional Symptoms

Many people with IgE-mediated (allergic) asthma develop occupational rhinitis (nasal allergy) symptoms before the onset of OA symptoms.

Symptoms from work-related exposures can happen right away or take years to develop.

Causes and Risk Factors

Regular exposure to fumes, gasses, dust, or other irritants causes OA. The exposure either directly damages airways or causes sensitization to the offending substance.

With sensitization, your body gradually develops an abnormal immune reaction to a substance. You're at risk for OA if you work in the following places:

• Bakery
• Detergent manufacturing facility
• Drug manufacturing facility
• Farm
• Grain elevator
• Laboratory (especially those that involve animals)
• Metal-processing facilities
• Mills
• Plastics manufacturing facility
• Woodworking facility

These and many other workplaces may expose you to potentially problematic substances.

Those who outgrew childhood asthma or have a family history of asthma, are more likely to develop the occupational type.

Additional Diagnostic Tests

If asthma is diagnosed and seasonal allergies are ruled out as a trigger, work-related causes will be investigated. It helps to provide Material Safety Data Sheets for chemicals you are exposed to at work.

The next steps can include:

• Testing for the allergen with a skin test or blood test
• Breathing tests throughout the workday
• Bronchoprovocation, or purposefully irritating the airways with the suspected trigger, to see if your lung function drops at least 20%

Occupational asthma is sometimes misdiagnosed as bronchitis. If the symptoms of diagnosed bronchitis are not helped with treatment or tend to be worse at work than elsewhere, bring this up with your healthcare provider.

Getting a proper diagnosis and treatment is important. If OA continues unchecked, it can cause permanent lung damage.

Additional Treatments

Standard asthma treatments are typically used for OA. The problem substance(s) should be avoided, if possible.

This may require Reasonable Accommodation from an employer, which is required under the Americans With Disabilities Act (ADA). Some people have to change jobs to avoid triggers.

Other Types of Asthma

Asthma has several less-common forms.

Obese Asthma

Obese asthma is a recently identified asthma type. It appears to be different from other types of asthma, even in people with obesity. Genetic studies suggest that airway constriction comes from a different mechanism.

Obese asthma is a stand-alone diagnosis. Research suggests it has a different genetic and molecular basis plus many other unique characteristics. Not everyone diagnosed with obesity who also has asthma has obese asthma.

Medication-Induced Asthma

Medication-induced asthma is triggered by aspirin and a few other medications. It is believed to be linked to genetic susceptibility.

This can be a stand-alone diagnosis, or it may be added to a previous asthma diagnosis. It typically makes pre-existing asthma worse and can be severe or even fatal.

Viral-Induced Asthma

In viral-induced asthma, a respiratory tract infection (e.g., a common cold, flu, COVID-19) can trigger or worsen asthma. An estimated 50% of acute asthma attacks have a viral trigger.

This type can also be a stand-alone or add-on diagnosis.

Glucocorticoid-Resistant Asthma

Glucocorticoid-resistant asthma is a subtype of asthma. It's defined by symptoms that don't respond to the steroid treatments frequently used for asthma. It's especially likely to be severe.

Glucocorticoid-resistant asthma is always an add-on to an earlier asthma diagnosis.

Classifying Different Types of Asthma

It's not uncommon for asthma to be called by several different names.

It may be referred to by its:

• Type (as discussed above)
• Frequency: intermittent or persistent
• Severity: mild, moderate, or severe (three levels)
• When it started: childhood-onset vs. adult-onset asthma

Asthma is also classified by the type of airway inflammation involved, including:

• Eosinophilic asthma is inflammatory asthma that is typically related to an allergic reaction.
• Neutrophilic asthma is inflammatory asthma associated with severe and persistent symptoms.
• Mixed eosinophilic and neutrophilic asthma is also possible.
• Paucigranulocytic asthma is non-inflammatory asthma.
  

Some of these classifications may also be combined—for example, mild intermittent adult-onset allergic asthma or glucocorticoid-resistant occupational asthma. It's also possible to have more than one type of asthma. For example, you could have non-allergic and nocturnal asthma.

If you're unsure what's behind the name being used to describe your case, be sure to ask your healthcare provider.

These are more than just names. They indicate something about your condition that is important to its management, among other things. For example, compared to childhood-onset asthma, adult-onset asthma typically:

• Is less likely to have periods of remission
• Involves constant breathing problems
• Leads to more rapid declines in lung function
• Is more difficult to treat
• Is less likely to be associated with allergies

Summary

Asthma comes in many forms and can develop at any age. Allergic asthma is triggered by allergies. Non-allergic asthma is triggered by airborne irritants. Less common types are triggered by certain medications or viruses.

Cough-variant asthma is distinguished by a dry cough. Nocturnal asthma is worse at night. Exercise-induced bronchoconstriction isn't true asthma but is common in people with asthma. Occupational asthma is triggered by workplace exposure to irritants.

An accurate asthma diagnosis means effective treatment. Pay close attention to symptoms, frequency, triggers, and other factors that can help your healthcare provider reach the correct diagnosis and treatment plan.