Doctors classify asthma based on what triggers your symptoms and how often they happen when making a diagnosis. Knowing your type and severity of asthma helps your allergist recommend the treatment that’s right for you.

In all types, symptoms of asthma can include wheezing, shortness of breath, chest tightness, coughing, and trouble breathing. When the only symptom of asthma is a dry cough, it may be referred to as cough-variant asthma.

What Are the Five Classifications of Asthma?

Asthma symptoms can be triggered by many different things, including certain substances, situations, and health conditions. It’s possible to have more than one type of asthma.

Allergic asthma is the most common type of asthma. About two-thirds of people with asthma also have allergies. It often begins in early childhood and becomes less frequent with age. At least 30 percent of adult-onset asthma cases are triggered by allergies. Allergic asthma is caused by an overreaction of the immune system in response to a normally harmless substance, known as an allergen. Allergens vary widely between people, but some of the most common allergens involved in allergic asthma are pollen, furry pets, mold, cockroaches, and dust mites.

Some people with allergic asthma receive immunotherapy, a treatment that helps the body build tolerance to the allergens that trigger their symptoms.

Nonallergic asthma is more common in adults, peaking in late adulthood. In people with nonallergic asthma, it can be more difficult to identify what triggers symptoms. Nonallergic asthma can be triggered by many different substances and situations.

For example, triggers can include stress, strong emotions, certain medicines, food additives, cold air or weather changes, and air pollution from car exhaust or smoke.

Up to 90 percent of people with asthma will experience exercise-induced bronchoconstriction (EIB), also known as exercise-induced asthma. For some people, a cough is the only symptom. Anyone, even people without asthma, can become short of breath after strenuous exercise. In people with EIB, exercise triggers bronchoconstriction — the narrowing of airways in the lungs.

The result is an attack of asthma symptoms that may begin during physical activity, worsen for a few minutes after activity is stopped, and last for about 30 minutes to an hour and a half. Some people with EIB have milder, late-phase symptoms that start a few hours after exercise and last for up to a day.

People who work in jobs where they’re exposed to airborne irritants, such as fumes or dust, may develop occupational asthma. About 10 percent to 25 percent of adults with asthma experience occupational asthma. If your asthma symptoms began when you started a job, improve when you’re away from your job, and become worse when you’re at work, you may have occupational asthma.

Professions with a higher risk for occupational asthma include bakers, farmers, laboratory workers, and those who manufacture pharmaceuticals, metals, plastics, and wood products.

Chronic obstructive pulmonary disease (COPD) is a lung condition that includes emphysema and chronic bronchitis. Asthma and COPD are separate conditions, but some people have both.

These conditions share some symptoms, including coughing, wheezing, and shortness of breath. This is sometimes called asthma-COPD overlap, although it isn’t considered a separate disease. People with both asthma and COPD tend to experience more frequent and severe symptoms, as well as reduced lung function. Having both COPD and asthma can complicate the diagnosis of breathing problems and lead to one condition or the other being missed. COPD is most commonly diagnosed in people aged 50 to 74 who smoke or used to smoke.

How Severe Are Your Symptoms?

In addition to classifying asthma by its triggers, doctors also assess it based on how often and how severe your symptoms are. In adults and children aged 5 or older, doctors will often measure forced expiratory volume in one second (FEV1) — the amount of air you can blow out in the first second of a forced breath.

The National Asthma Education and Prevention Program has established criteria for classifying asthma severity.

Intermittent Asthma

Intermittent asthma is diagnosed when asthma symptoms:

Mild Persistent Asthma

Mild persistent asthma is diagnosed when asthma symptoms:

Moderate Persistent Asthma

Moderate persistent asthma is diagnosed when asthma symptoms:

Severe Persistent Asthma

Severe persistent asthma is diagnosed when asthma symptoms:

Healthcare providers classify asthma severity to determine which asthma medications are most appropriate. Your asthma classification can change over time. It’s important to remember that it’s possible to have a severe asthma attack, no matter how your asthma is classified.