Asthma: Defined


Asthma is a chronic lung disease that affects more than 25 million people in the United States, according to the National Heart, Lung, and Blood Institute.

Patients with asthma often have trouble breathing and sleeping through the night without having a coughing fit. This is because asthma inflames patients’ airways and causes them to narrow, which can prevent air from reaching the lungs efficiently.

Asthma can range in severity from minor trouble breathing to major asthma attacks, which can be deadly.

Although there is no cure for asthma, treatment for the disease is advanced enough to allow most patients to live normal, healthy lives.


diagram of health and asthmatic airwaysAsthma symptoms can vary significantly for each patient. Some asthma patients may never experience chest tightness but may have intermittent asthma attacks, while others have very serious symptoms triggered by allergens like pollen or pets.

Common symptoms include shortness of breath, coughing more at night or in the morning, trouble sleeping due to coughing or wheezing, and a whistling sound when exhaling.

Because asthma severity varies so widely, some patients have worse symptoms in particular situations. These situations might include exposure to allergens like pet dander, exercising and working in an environment with airborne irritants like dust.


To diagnose asthma, your doctor will likely assess your medical and family history and give you a physical exam. Depending on the test results, your doctor may diagnose you with asthma.

The doctor usually asks the patient about symptom severity and frequency. If your symptoms tend to worsen at night or in the morning, be sure to let your doctor know, as this may be a sign of asthma.

For the physical exam, your doctor will likely want to assess your breathing to look for symptoms like wheezing and congestion.

The most common diagnostic test for asthma is called spirometry. This lung function test measures how efficiently your lungs breathe in and expel air.

If your lungs don’t seem to work very well, your doctor may diagnose you with asthma. But your doctor may need more information to, for example, rule out other conditions like extreme allergies or chronic obstructive pulmonary disease (COPD). To obtain this information, he or she might give you an X-ray or allergy testing.


There are many treatments for asthma. In addition to inhalers and medications, a common aspect of treatment is identifying what triggers your asthma and avoiding it. For instance, if you have a severe allergic reaction to dust, your doctor would tell you to avoid exposure to dusty environments, such as old houses.

Short-term treatment for asthma is usually an inhaler. These fast-acting medicines are usually steroids like albuterol. When you have an asthma attack or feel one coming on, you inhale the medication from the inhaler. These medications work to quickly open blocked airways.

Long-term medication is key to asthma treatment. Such medications are usually taken daily and reduce the likelihood of an asthma attack. Notable among the many long-term asthma medications are leukotriene modifiers like montelukast (brand name Singulair) and zileuton (brand name Zyflo).

In some cases, doctors will also prescribe allergy medications, which include allergy shots and daily allergy medications like nasal spray (brand name Afrin) and antihistamines (brand name Benadryl).

Many doctors prescribe what’s called an asthma action plan. This is a written plan that details when you should take your medications and adjust doses based on how you’re feeling. It also includes a list of items or situations that often trigger asthma attacks for you.


Despite the large amount of research conducted on the subject, the cause of asthma remains unknown. The general consensus among scientists, however, is that the cause is influenced by a combination of genetic and environmental factors.

For example, researchers have associated some respiratory infections in early childhood with an increased risk of asthma, but they’ve also associated an increased risk with having parents who also have asthma.

Living With

An asthma action plan is a good first step to living with asthma. The key is learning to control and manage your asthma symptoms. The action plan combined with regular doctor visits can greatly improve asthma patients’ quality of life.

Always be vigilant. If your asthma appears to be getting worse or you have a new symptom, immediately let your doctor know.

Getting Help

Doctors are the only people qualified to diagnose or treat your asthma. However, health organizations often maintain online resources and publish research dedicated to making life with asthma easier.

For example, the National Heart, Lung, and Blood Institute has a sample asthma action plan on its website to help you get started with your own.

Related Information

Because asthma can affect your ability to breathe properly, it can lead to several complications — especially if left untreated.

Complications of asthma include insomnia, airway remodeling (a permanent constriction of the bronchial tubes) and various side effects from using asthma medications for long periods of time.

Mayo Clinic, “Asthma”

Centers for Disease Control and Prevention, “Asthma”

National Heart, Lung and Blood Institute, “What Is Asthma?”

National Heart, Lung, and Blood Institute, “Asthma Action Plan”