Daniel More, MD, is a board-certified allergist and clinical immunologist. He is an assistant clinical professor at the University of California, San Francisco School of Medicine and currently practices at Central Coast Allergy and Asthma in Salinas, California.
Asthma is a chronic lung disease. When you have asthma, your airways may react to a number of different triggers, such as smoke, allergens like pollen, or infections. This leads to constricted and inflamed airways, resulting in airflow obstruction and making it difficult to breathe.
The classic symptoms of asthma are wheezing, chest tightness, shortness of breath, and cough. Asthma can be treated with medications that help control the condition from day to day, while rescue inhalers treat acute attacks of narrowed airways.
Many people manage this condition successfully with the help of medication and by learning their personal triggers and making lifestyle changes. However, if your asthma symptoms become severe, it is considered a medical emergency. Call 911 or seek help right away.
While its causes are still not entirely understood, asthma is frequently related to genetic factors—people with a family history of asthma are two to six times more likely to develop it themselves. It can also develop after exposure to respiratory infections, allergens, or irritants during childhood or in the workplace.
In addition to evaluating your symptoms—such as shortness of breath, wheezing, or coughing—your doctor may check your breathing with lung (pulmonary) function tests as well as your response to treatment with bronchodilators. Experiencing asthma symptoms that resolve upon treatment with medication is generally considered sufficient for a diagnosis of asthma.
While asthma is not curable, it is highly treatable. Many people manage this condition successfully over the long term with the help of medication and by learning their personal triggers and making other lifestyle changes.
Recent research suggests there may be a link between asthma and autoimmune diseases, which are both the result of an overactive immune system. People with asthma are more likely to develop certain autoimmune diseases, such as type 1 diabetes, myasthenia gravis, and lupus. Mast cell activation—a prominent feature of asthma—is also believed to be involved in the symptoms of autoimmune diseases like rheumatoid arthritis and multiple sclerosis.
An allergen is a substance that triggers an immune response in the body—specifically, an IgE antibody response. Allergens vary from person to person and can include a variety of substances, such as mold, food, medications, insect stings, animal dander, dust mites, and metals. Allergic asthma is often triggered by such allergens.
An inhaler is an alternative to a nebulizer machine. An inhaler may be more difficult to use, particularly for children, because it requires coordination to deliver the medication to your lungs (rather than mouth). When an inhaler is used with a spacer, however, this awkwardness can usually be overcome, and more consistent doses of medication are delivered to the lungs as compared to a nebulizer.
A nebulizer turns liquid medication into a fine mist that can be inhaled into the lungs via a mouthpiece or mask. Some nebulizers are portable (working via a battery), while others require electricity. Nebulizers may be easier to use when airways are inflamed during an asthma attack, but there is evidence they don’t deliver medicine as effectively as metered dose inhalers.
A pulmonary (lung) function test measures your ability to breathe and take in oxygen. In the most common type of pulmonary test, you’ll breathe into a device called a spirometer, which evaluates the amount of air you blow out in each breath and the speed at which you can do so. Pulmonary function may also be measured with other types of testing, such as plethysmography.
Liu, T., Valdez, R., Yoon, P. et al. The association between family history of asthma and the prevalence of asthma among US adults: National Health and Nutrition Examination Survey, 1999–2004. Genet Med 11, 323–328 (2009). doi:10.1097/GIM.0b013e31819d3015
Mukherjee M, Nair P. Autoimmune responses in severe asthma. Allergy Asthma Immunol Res. 2018;10(5):428-47. doi:10.4168/aair.2018.10.5.428