Asthma
Asthma is a chronic disease that causes the airways of the lungs to swell and narrow. It leads to breathing difficulty such as wheezing, shortness of breath, chest tightness, and coughing.
Asthma - Animation
Breathing is something we do without even thinking about it. But some people have a hard time breathing easily. They wheeze, cough, and just can't get enough air into their lungs. Let's talk about asthma. Normally when you breathe, oxygen-rich air enters your nose and mouth and travels to the airways in your lungs. But when you have an asthma attack, the muscles in your airways tighten. Your airways swell up and get narrower. It's like pressing on a straw when you're trying to drink through it. The more you press, the less of your drink can squeeze up through the straw. In the same way, less air can squeeze through tight airways into your lungs. So, what causes asthma? People with asthma have different triggers. Some people are sensitive to pet hair or dander. Others find that dust, pollen, smoke, or chemicals make them wheeze. You may have trouble breathing when you're under stress or working out at the gym. Often people with asthma have allergies that trigger their attacks. Others have a parent or other relative who has allergies. You may ask, how can you know for sure that you have asthma? During an asthma attack, you'll have trouble breathing. You may cough or wheeze as you try to draw air into your lungs. If you're having a severe attack, your lips and face may turn blue and you'll have a hard time getting any air. That's when it's time to call for emergency help. Your doctor will listen to your lungs with a stethoscope, and may do other tests to check your blood and lung function. To find out what's triggering your asthma, you may need to be tested for allergies to mold, pollen, pet dander, or other substances. To measure the strength of air flowing out of your lungs, you'll blow into a device called a peak flow meter. You can also use a peak flow meter to make sure you're keeping your asthma under control. Different medicines are used to prevent and treat asthma. Control drugs help you avoid asthma attacks, but you need to take them every day for them to work. You breathe in control drugs like Flovent and Pulmicort through an inhaler. If you're having an asthma attack, you can take a quick-relief drug to control your wheezing. Examples of quick-relief drugs include short-acting inhaled drugs and steroid medicines that you take by mouth. When you have asthma, you need to be prepared. Know your asthma triggers and try to avoid them. Carry an inhaler with you in case you have an asthma attack. If you ever have an attack that's so severe you can't breathe, call 911 or get emergency medical help.
Causes
Asthma is caused by swelling (inflammation) in the airways. An asthma attack occurs when the lining of the air passages has become swollen and the muscles surrounding the airways become tight. This narrowing reduces the amount of air that can pass through the airway.
Normal versus asthmatic bronchiole
During an asthma attack smooth muscles located in the bronchioles of the lung constrict and decrease the flow of air in the airways. The amount of air flow can further be decreased by inflammation or excess mucus secretion.
Asthma symptoms can be caused by breathing in substances called allergens or triggers, or by other causes.
Allergens
An allergen is a substance that can cause an allergic reaction. In some people, the immune system recognizes allergens as foreign or dangerous. As ...
Common asthma triggers include:
- Animals (pet hair or dander)
- Dust mites
- Certain medicines (aspirin and other NSAIDs)
- Changes in weather (most often cold weather)
- Chemicals in the air (pollution) or in food
- Physical activity
- Mold
- Pollen
- Respiratory infections, such as the common cold and many other viruses
Common cold
The common cold most often causes a runny nose, nasal congestion, and sneezing. You may also have a sore throat, cough, headache, or other symptoms....
ImageRead Article Now Book Mark Article - Strong emotions (stress)
- Tobacco or other inhalant that is smoked
Substances in some workplaces can also trigger asthma symptoms, leading to occupational asthma. The most common triggers are wood dust, grain dust, animal dander, fungi, or chemicals.
Occupational asthma
Occupational asthma is a lung disorder in which substances found in the workplace cause the airways of the lungs to swell and narrow. This leads to ...
Many people with asthma have a personal or family history of allergies, such as hay fever (allergic rhinitis) or eczema. Others have no history of allergies.
Allergies
An allergy is an immune response or reaction to substances that are usually not harmful.
Allergic rhinitis
Allergic rhinitis is a diagnosis associated with a group of symptoms affecting the nose. These symptoms occur when you breathe in something you are ...
Eczema
Atopic dermatitis is a long-term (chronic) skin disorder that involves scaly and itchy rashes. It is a type of eczema. Other forms of eczema include...
Common asthma triggers
Many of the same substances that trigger allergies can also trigger asthma. Common allergens include pollen, dust mites, mold and pet dander. Other asthma triggers include irritants like smoke, pollution, fumes, cleaning chemicals, and sprays. Asthma symptoms can be substantially reduced by avoiding exposure to known allergens and respiratory irritants.
Symptoms
Asthma symptoms vary from person to person. For example, you may have symptoms all the time or mostly during physical activity.
Most people with asthma have attacks separated by symptom-free periods. Some people have long-term shortness of breath with episodes of increased shortness of breath. Wheezing or a cough may be the main symptom.
What causes wheezing? - Animation
Wheezing can be a normal healthy response to an unhealthy environment. Or, wheezing can be a sign of asthma. I'm Dr. Alan Greene and I want to talk with you for a moment about how to tell the difference, what causes wheezing anyway, and when is it healthy and when is it not. Well to understand that, first let's all take a deep breath together (inhales). When you breathe in, the air comes through your nose or mouth, through the big windpipe and breaks into 2 big bronchi, one into each lung. And from there they break into a whole bunch of little, smaller bronchioles. It's almost like a tree's branches branching out. And those bronchioles are where the wheezing happens. Let's look at a bronchiole. Here's one of those small airways. Now if you happen to walk into a cloud of something that's toxic, your body is going to respond instantly to try to protect you. The first thing that will happen is the muscles around the bronchioles will tighten, will constrict down almost like a boa constrictor, and you get the tight airways. If that toxic cloud is still there, to protect your delicate tissues deep in your lungs, swelling of the lining will happen. Inflammatory stuff to help protect you from those toxins. And if it's still there, still irritating, mucus will begin to be secreted to be able again to capture and protect you from those toxins. That's wheezing. Asthma happens when your airways are hyper-responsive. When they're twitchy. When they're hyper-alert and they respond to something that's not truly dangerous. The problem with that is when your bronchioles are constricted and swollen and has mucus in them, that narrow little opening is hard to breathe through. You have to work to breathe, especially to breath out. And that hard breathing through a narrow passageway is what creates the sound we know as wheezing.
Asthma attacks can last for minutes to days. An asthma attack may start suddenly or develop slowly over several hours or days. It may become dangerous if airflow is severely blocked.
Symptoms of asthma include:
- Cough with or without sputum (phlegm) production
Cough
Coughing is an important way to keep your throat and airways clear. But too much coughing may mean you have a disease or disorder. Some coughs are d...
ImageRead Article Now Book Mark Article - Pulling in of the skin between the ribs when breathing (intercostal retractions)
Intercostal retractions
Intercostal retractions occur when the muscles between the ribs pull inward. The movement is most often a sign that the person has a breathing probl...
Read Article Now Book Mark Article - Shortness of breath that gets worse with exercise or activity
Shortness of breath
Breathing difficulty may involve:Difficult breathing Uncomfortable breathingFeeling like you are not getting enough air
ImageRead Article Now Book Mark Article - Whistling sound or wheezing as you breathe
- Pain or tightness in the chest
Pain or tightness in the chest
Chest pain is discomfort or pain that you feel anywhere along the front of your body between your neck and upper abdomen.
ImageRead Article Now Book Mark Article - Difficulty sleeping
- Abnormal breathing pattern (breathing out takes more than twice as long as breathing in)
Emergency symptoms that need prompt medical help include:
- Bluish color to the lips and face (cyanosis)
Bluish color
A bluish color to the skin or mucous membrane is usually due to a lack of oxygen in the blood. The medical term is cyanosis.
ImageRead Article Now Book Mark Article - Decreased level of alertness, such as severe drowsiness or confusion, during an asthma attack
- Extreme difficulty breathing
Difficulty breathing
Breathing difficulty may involve:Difficult breathing Uncomfortable breathingFeeling like you are not getting enough air
ImageRead Article Now Book Mark Article - Rapid pulse
Rapid pulse
A bounding pulse is a strong throbbing felt over one of the arteries in the body. It is due to a forceful heartbeat.
ImageRead Article Now Book Mark Article - Severe anxiety due to shortness of breath
Anxiety
Stress is a feeling of emotional or physical tension. It can come from any event or thought that makes you feel frustrated, angry, or nervous. Stres...
ImageRead Article Now Book Mark Article - Sweating
Sweating
Sweating is the release of liquid from the body's sweat glands. This liquid contains salt. This process is also called perspiration. Sweating helps...
ImageRead Article Now Book Mark Article - Difficulty speaking
- Breathing temporarily stops
Exams and Tests
The health care provider will use a stethoscope to listen to your lungs. Wheezing or other asthma-related sounds may be heard. The provider will take your medical history and ask about your symptoms.
Tests that may be ordered include:
- Allergy testing -- a skin test or a blood test to see if a person with asthma is allergic to certain substances
Skin
Allergy skin tests are used to find out which substances cause a person to have an allergic reaction. These substances are called allergens....
ImageRead Article Now Book Mark ArticleBlood test
An absolute eosinophil count is a blood test that measures the number of one type of white blood cells called eosinophils. Eosinophils become active...
ImageRead Article Now Book Mark Article - Arterial blood gas -- often done in people who are having a severe asthma attack
Arterial blood gas
Blood gases are a measurement of how much oxygen and carbon dioxide are in your blood. They also determine the acidity (pH) of your blood.
ImageRead Article Now Book Mark Article - Chest x-ray or CT scan of the chest -- to check other conditions
Chest x-ray
A chest x-ray is an x-ray of the chest, lungs, heart, large arteries, ribs, and diaphragm.
ImageRead Article Now Book Mark Article - Lung function tests, including peak flow measurements
Lung function tests
Pulmonary function tests are a group of tests that measure breathing and how well the lungs are functioning.
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Treatment
The goals of treatment are to:
- Control airway swelling
- Limit exposure to substances that may trigger your symptoms
Limit exposure to substances that may t...
It is important to know what things make your asthma worse. These are called asthma "triggers. " Avoiding them is your first step toward feeling bet...
ImageRead Article Now Book Mark Article - Help you to be able to do normal activities without having asthma symptoms
You and your provider should work as a team to manage your asthma symptoms. Follow your provider's instructions on taking medicines, eliminating asthma triggers, and monitoring symptoms.
MEDICINES FOR ASTHMA
There are two kinds of medicines for treating asthma:
- Control medicines to help prevent attacks
- Quick-relief (rescue) medicines for use during attacks
LONG-TERM MEDICINES
Control medicines for asthma are medicines you take to control your asthma symptoms. You must use these medicines every day for them to work well. ...
These are also called maintenance or control medicines. They are used to prevent symptoms in people with moderate to severe asthma. You must take these medicines every day for them to work. Take them even when you feel OK.
Some long-term medicines are breathed in (inhaled), such as steroids and long-acting beta-agonists. Others are taken by mouth (orally). Your provider will prescribe the right medicine for you.
QUICK-RELIEF MEDICINES
Asthma quick-relief medicines work fast to control asthma symptoms. You take them when you are coughing, wheezing, having trouble breathing, or havi...
These are also called rescue medicines. They are taken:
- For coughing, wheezing, trouble breathing, or during an asthma attack
- Just before physical activity to help prevent asthma symptoms
Tell your provider if you are using quick-relief medicines twice a week or more. If so, your asthma may not be under control. Your provider may change the dose or your daily asthma control medicine to reduce the use of quick-relief medicines.
Quick-relief medicines include:
- Short-acting inhaled bronchodilators
- Oral corticosteroids for a severe asthma attack
A severe asthma attack requires a checkup by a provider. You may also need a hospital stay. There, you will likely be given oxygen, breathing assistance, and medicines given through a vein (IV).
ASTHMA CARE AT HOME
You can take steps to decrease the possibility of asthma attacks:
- Know the asthma symptoms to watch for.
Asthma symptoms to watch for
If you do not know whether or not you have asthma, these 4 symptoms could be signs that you do:Coughing during the day or coughing that may wake you ...
Read Article Now Book Mark Article - Know how to take your peak flow reading and what it means.
- Know which triggers make your asthma worse and what to do when it happens.
Know which triggers
It is important to know what things make your asthma worse. These are called asthma "triggers. " Avoiding them is your first step toward feeling bet...
ImageRead Article Now Book Mark Article - Know how to care for your asthma before and during physical activity or exercise.
Before and during physical activity or ...
Sometimes exercise triggers asthma symptoms. This is called exercise-induced bronchoconstriction (EIB). In the past, this was called exercise-induc...
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Asthma action plans are written documents for managing asthma. An asthma action plan should include:
- Instructions for taking asthma medicines when your condition is stable
- A list of asthma triggers and how to avoid them
- How to recognize when your asthma is getting worse, what to do and when to call your provider
A peak flow meter is a simple device to measure how quickly you can move air out of your lungs.
Peak flow meter
Checking your peak flow is one of the best ways to monitor your asthma and to keep it from getting worse. Asthma attacks do not usually come on witho...
Read Article Now Book Mark Article- It can help you see if an attack is coming, sometimes even before symptoms appear. Peak flow measurements help let you know when you need to take medicine or other action.
- Peak flow values of 50% to 80% of your best results are a sign of a moderate asthma attack. Numbers below 50% are a sign of a severe attack.
Outlook (Prognosis)
There is no cure for asthma, although symptoms sometimes improve over time. With proper self-care and medical treatment, most people with asthma can lead a normal life.
Possible Complications
The complications of asthma can be severe, and may include:
- Death
- Decreased ability to exercise and take part in other activities
- Lack of sleep due to nighttime symptoms
- Permanent changes in the function of the lungs
- Persistent cough
- Trouble breathing that requires breathing assistance (ventilator)
When to Contact a Medical Professional
Contact your provider for an appointment if asthma symptoms develop.
Contact your provider right away if:
- An asthma attack requires more medicine than recommended
- Symptoms get worse or do not improve with treatment
- You have shortness of breath while talking
- Your peak flow measurement is 50% to 80% of your personal best
Go to the emergency room right away if these symptoms occur:
- Drowsiness or confusion
Confusion
Confusion is the inability to think as clearly or quickly as you normally do. You may feel disoriented and have difficulty paying attention, remembe...
ImageRead Article Now Book Mark Article - Severe shortness of breath at rest
- A peak flow measurement of less than 50% of your personal best
- Severe chest pain
Chest pain
Chest pain is discomfort or pain that you feel anywhere along the front of your body between your neck and upper abdomen.
ImageRead Article Now Book Mark Article - Bluish color to the lips and face (cyanosis)
- Extreme difficulty breathing
- Rapid pulse
- Severe anxiety due to shortness of breath
Prevention
You can reduce asthma symptoms by avoiding triggers and substances that irritate the airways.
- Cover bedding with allergy-proof casings to reduce exposure to dust mites.
- Remove carpets from bedrooms and vacuum regularly.
- Use only unscented detergents and cleaning materials in the home.
- Keep humidity levels low and fix leaks to reduce the growth of organisms such as mold.
- Keep the house clean and keep food in containers and out of bedrooms. This helps reduce the possibility of cockroaches. Body parts and droppings from cockroaches can trigger asthma attacks in some people.
- If someone is allergic to an animal that cannot be removed from the home, the animal should be kept out of the bedroom. Place filtering material over the heating/air conditioning outlets in your home to trap animal dander. Change the filter in furnaces and air conditioners often.
- Eliminate tobacco smoke from the home. This is the single most important thing a family can do to help someone with asthma. Smoking outside the house is not enough. Family members and visitors who smoke outside carry smoke residue inside on their clothes and hair. This can trigger asthma symptoms. If you smoke, now is a good time to quit.
Tobacco smoke
Things that make your allergies or asthma worse are called triggers. Smoking is a trigger for many people who have asthma.
Read Article Now Book Mark Article - Avoid air pollution, industrial dust, and irritating fumes as much as possible.
Reviewed By
Denis Hadjiliadis, MD, MHS, Paul F. Harron, Jr. Professor of Medicine, Pulmonary, Allergy, and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA. Internal review and update on 02/10/2024 by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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Cloutier MM, Dixon AE, Krishnan JA, Lemanske RF Jr, Pace W, Schatz M. Managing Asthma in Adolescents and Adults: 2020 Asthma Guideline Update From the National Asthma Education and Prevention Program. JAMA. 2020;324(22):2301-2317. PMID: 33270095 pubmed.ncbi.nlm.nih.gov/33270095/.
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