shortness of breath Alternative Names
dyspnoea, trouble breathing, difficulty breathing, SOB
People with shortness of breath feel as though they can't get enough air or are "out of breath."
What is going on in the body?
Shortness of breath can be due to many different causes. It is normal with strenuous activity. An affected person has the feeling of "air hunger," as though they cannot take in enough air. Breathing heavily may or may not make the person feel better.
What are the signs and symptoms of the condition?
Doctors often ask about several things when a person has shortness of breath. These questions may include:
Other questions may be asked, based on the answers to these questions.
- when the condition started
- whether it came on suddenly or gradually
- whether it occurs at rest or only during activity
- whether it is worse when lying down or sitting up
- how many pillows the person sleeps with
- whether the person has any history of heart or lung disease
- whether the person has any other symptoms, such as fever, cough, swelling in the legs, chest pain, or anxiety
- whether anyone in the family has shortness of breath
- whether or not the person smokes
What are the causes and risks of the condition?
The many causes of shortness of breath can be divided into categories:
Other causes are also possible. In some cases, the cause cannot be found.
- exercise or other activity, especially if the person is in poor physical shape
- lung conditions, such as asthma, pneumonia, chronic bronchitis, Lung cancer, pulmonary oedema, or emphysema
- heart conditions, such as stable angina, a heart attack, congestive heart failure, or chronic mitral regurgitation
- blood and blood vessel problems, such as anaemia or a pulmonary embolism
- anxiety, such as from a panic disorder
- too much acid in the blood, which can occur with diabetes, serious blood infections such as septicaemia, salt imbalances or severe dehydration
- rapid ascent to high altitudes without allowing the body time to adjust, known as acute mountain sickness
- cigarette smoking
- airway obstruction, such as in a child who may have choked on an object
What can be done to prevent the condition?
Prevention depends on the cause. For example, avoiding strenuous activity can prevent shortness of breath. Regular exercise can get people in shape so they're less likely to get short of breath with normal activity. Many cases of shortness of breath from asthma, congestive heart failure, and panic disorders can be prevented by taking medications regularly. Many cases cannot be prevented.
How is the condition diagnosed?
Diagnosis of the cause of shortness of breath begins with a history and physical examination. This may be all that is needed. But usually more tests have to be done, and they are based on the suspected condition. Blood tests and chest x-rays are commonly performed. Other tests may include an ECG, or electrocardiogram, which measures the electrical activity in the heart. An ECG can often help diagnose heart conditions that may be causing shortness of breath. Other tests may be needed in some cases, such as special x-rays or breathing tests.
What are the long-term effects of the condition?
Long-term effects are related to the cause. For example, shortness of breath due to exercise has no long-term effects and is usually encouraged. pneumonia treated with antibiotics often goes away and causes no long-term effects. Shortness of breath due to lung cancer may result in death. Heart attacks and congestive heart failure may cause serious disability and limit a person's ability to perform normal activities.
What are the risks to others?
Most causes of shortness of breath are not contagious and pose no risk to others. But if the cause is an infection like Pneumonia, it may be contagious.
What are the treatments for the condition?
Treatment is directed at the cause. For example, asthma, congestive heart failure, and emphysema are usually treated with regular medications to prevent shortness of breath. Lung or blood infections are often treated with antibiotics. lung cancer may require surgery, radiation therapy, or chemotherapy. People with anaemia, or low blood counts, may need a blood transfusion.
What are the side effects of the treatments?
All medications have possible side effects. These may include allergic reactions, stomach upset, and headaches. Specific side effects depend on the medications used. Surgery carries a risk of bleeding, infection, and reaction to any analgesics used. More specific side effects depend on the surgery done. Blood transfusions carry a risk of allergic reactions and infections.
What happens after treatment for the condition?
This depends on the cause of shortness of breath. If the underlying cause goes away, no further treatment may be needed. In these cases, people can return to normal activities as soon as they feel able. Other people, such as those with emphysema, may need treatment for life.
How is the condition monitored?
Monitoring also depends on the cause. For example, people with anaemia may need blood tests to make sure their blood counts have returned to normal.
Author: Adam Brochert, MD
Reviewer: HealthAnswers Australia Medical Review Panel
Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia
Last Updated: 1/10/2001
Potential conflict of interest information for reviewers available on request