Medically reviewed by Dr. C.H. Weaver M.D. updated 2/2021
Asthma is a disease that affects your lungs. This chronic, long-term condition inflames and narrows your airways, which results in wheezing, chest tightness, shortness of breath, and coughing (asthma-related coughing usually occurs at night or early in the morning).
Asthma occurs when the airways, or tubes that carry air in and out of your lungs, become inflamed, or swollen, and react to certain inhaled substances (known as triggers). This reaction includes tightening of the muscles surrounding the airways, which causes the airways to narrow and allows less air to pass through. The airways may then swell more and make more mucus, further narrowing the airways and making it more difficult to breath.
Asthma may be caused by several factors, both genetic (meaning that asthma runs in your family) and environmental.
Asthma often starts during childhood but can affect people of all ages. More than 22 million people in the United States, including 6 million children, are known to have asthma.
Symptoms of Asthma
If you have asthma, you may find that your symptoms vary. They may be mild at times and easy to treat, or they may sometimes be more severe. Intense asthma symptoms are considered an asthma attack.
Symptoms of asthma include:
- Chest tightness
- Shortness of breath
- Coughing, usually at night or early in the morning
Symptoms of asthma may be triggered by the following:
- Allergens found in dust, animal fur, cockroaches, mold, and pollens from trees, grasses, and flowers
- Irritants such as cigarette smoke, air pollution, chemicals or dust in the workplace, and compounds in sprays (such as hairspray)
- Medicines including aspirin and other nonsteroidal anti-inflammatory drugs and nonselective beta-blockers (used to treat heart conditions)
- Sulfites in foods and drinks
- Colds and other upper-respiratory viruses
- Physical activity
Tests and Diagnosis
Your first step in determining if you have asthma is to visit your primary care doctor. A diagnosis of asthma is made using a physical examination, your medical and family history, and results from tests. If you are diagnosed with asthma, your doctor will also determine whether you have intermittent, mild, moderate, or severe asthma—this information will be used to plan your treatment.
One of the tests that will help determine if you have asthma is called a lung function test. This test uses a spirometry to test your lung function. It measures how much air you can breathe in and out and how quickly you can blow air out. Other possible tests include allergy testing, a bronchoprovocation test (which measures airway sensitivity), tests for other diseases that have symptoms similar to asthma (such as reflux disease, sleep apnea, or vocal cord dysfunction), and a chest X-ray or EKG.
Diagnosis in Children
It’s difficult to diagnose asthma in children younger than age five, which is when most children first develop symptoms. A lung function test is hard to perform on children this age. As well, symptoms of asthma and other childhood conditions can be similar, so doctors assess risk for asthma by considering the following: whether one or both parents have asthma; whether the child has signs of allergies, including the skin condition eczema; whether the child has allergic reactions to airborne allergens such as pollen; whether the child wheezes even when he or she doesn’t have a cold or other infection.
Treatments for Asthma
There is no cure for asthma, but with effective treatment and lifestyle measures to reduce your exposure to triggers, you can control symptoms. With good control, asthma won’t interfere with your daily life and activities and you’ll be at a reduced risk of asthma attacks that could require emergency treatment.
Medicines to Control Asthma
The two types of medicines used to control asthma are long-term control medicines and quick-relief medicines.
- Long-term control medicines are taken daily (using an inhaler or in a pill) to help reduce inflammation in your airways in order to prevent symptoms. They don’t provide quick relief when symptoms develop. Inhaled corticosteroids are considered the preferred medicine for long-term control. One possible side effect of inhaled corticosteroids is a mouth infection called thrush. You can reduce your risk of thrush by using a spacer or holding chamber, which attaches to your inhaler and keeps the medicine from landing in your mouth or the back of your throat. When taken over long periods, inhaled corticosteroids may also increase your risk of developing cataracts or osteoporosis. Ask your doctor about these and other side effects and how you may manage or avoid them.
- Quick-relief medicines are used to relieve symptoms when they do flare up and are taken using an inhaler. They work by relaxing tight muscles around the airways and allowing more air to flow through them. Quick-relief medications do not reduce inflammation, so they shouldn’t be used in place of long-term control medicines. You should carry your quick-relief inhaler at all times. Caregivers of children with asthma should always carry the child’s quick-relief inhaler.
Reducing Your Exposure to Triggers
Measures to avoid things that trigger your asthma symptoms may include staying indoors when pollen or air pollution levels are high, avoiding secondhand smoke, keeping pets out of your home or bedroom, vacuuming or sweeping frequently to control dust, and taking measures to keep your home free of cockroaches. If allergies trigger your asthma and you can’t avoid those allergens, you may consider getting allergy shots.
When to See a Specialist
If any of the following conditions apply to you, you may be referred to an asthma specialist: you need special tests to determine if you have asthma, you’ve had a life-threatening asthma attack, you need more than one kind of medicine or higher doses of medicine to control your asthma, you’ve had difficulty controlling your asthma, or you’re considering getting allergy treatments.
Living with Asthma
The key to living a full, active life with asthma is to develop and follow a personal asthma action plan. Together with your doctor, determine what kind of medicines to take daily and when to take them. Also know when to call your doctor or when to go to the emergency room.
As part of your action plan, you’ll also avoid exposures that trigger your asthma symptoms. Measures to avoid triggers are explained above in Treatments for Asthma.
Use a peak flow meter to measure how well air moves out of your lungs. This small, handheld device gives you a score called a peak flow number. Your doctor will tell you how and when to use a peak flow meter and what kind of information you should record. You’ll start by determining your personal best peak flow number, which is done by recording your score for two to three weeks when your asthma is under good control. The highest number during this period is your personal best. This number can be useful for determining how well your asthma is under control, and a lower number can help warn you of an asthma attack.
Monitor and record your symptoms so that you can measure how well your treatments are controlling your asthma. Signs of good control include: symptoms occurring no more than two days per week and one or two nights per month; ability to carry out normal activities; and use of quick-relief medicines no more than two days per week.
When to Call Your Doctor
- Your medicines don’t relieve an asthma attack
- Your peak flow is less than half of your personal best peak flow number
When to Call 9-1-1 for Emergency Care
- You have trouble walking and talking because you’re out of breath
- You have blue lips or fingernails
- Asthma. Centers for Disease Control and Prevention website. Available at: http://www.cdc.gov/asthma/. (Accessed October 2021).
- Asthma. National Heart, Blood, and Lung Institute website. Available at: http://www.nhlbi.nih.gov/health/dci/Diseases/Asthma/Asthma_All.html. (Accessed October 2021).
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