Dyspnea (Shortness of Breath)

Last Updated 08/11/2022

Author:Alan Roth, RRT, MS, FCCP, and Sai Praveen Haranath, MBBS, MPH, FCCP

About Shortness of Breath

Shortness of breath (medically known as “dyspnea”) is the sensation of not being able to get enough air. It can be either acute shortness of breath (minutes to hours), chronic (days to months), or intermittent (comes and goes). It is often described as a tightness in the chest, difficulty breathing, a feeling of breathlessness, or a sensation of suffocation. While there are many causes of shortness of breath, the most common causes are lung disease, heart disease, or deconditioning (lack of exercise, especially in people who are overweight or obese). It can also be seen in diseases that cause muscle weakness or disorders where fluid builds up around the lung (known as pleural effusions) or in the abdomen (known as ascites). Unexplained shortness of breath should be discussed with your physician to allow appropriate work-up to determine the cause.

Key facts about Shortness of Breath
  • Shortness of breath, or breathlessness, is discomfort or difficulty breathing. The medical term for shortness of breath is dyspnea.
  • Shortness of breath is a common symptom. It may be related to serious diseases, or it could be a result of being out of shape physically.
  • Your health care provider should assess whether shortness of breath is treatable with lifestyle changes, such as quitting smoking or losing weight.
  • Serious conditions associated with shortness of breath include:
  • Asthma
  • Chronic obstructive pulmonary disease (COPD)
  • Heart disease (heart attack, heart failure)
  • Anemia
  • Blood clots in the lungs, also called pulmonary embolism

Causes of Shortness of Breath

Heart and lung conditions cause most cases of shortness of breath. You may feel shortness of breath for many reasons. Factors can include your overall health, medical history, and genetics. Talk to a health care provider to find out more about why you feel shortness of breath.

Acute Shortness of Breath

Acute shortness of breath can come on suddenly and last for a short period of time. Causes include:

Lung conditions:

Heart conditions:

  • Heart attack
  • Heart failure
  • Heart rhythm disorder (arrhythmia)
  • Increased fluid around the heart

Psychological conditions:

  • Anxiety
  • Depression
  • Panic attacks

Chronic Shortness of Breath

Shortness of breath can also be chronic, meaning it lasts for several weeks or longer. Causes include:

You may be shocked to learn that while respiratory diseases can cause shortness of breath, so can major non-respiratory diseases such as anemia, cardiovascular disease, heart failure, deconditioning, and psychological disorders. It’s important to understand all of the causes of shortness of breath to ensure that you get a proper diagnosis and undergo the appropriate treatment.

Shortness of Breath: An Overview

Physiology of Shortness of Breath

Normally, there’s a balance between the demand to breathe and ability to breathe. When there’s a balance, you have no awareness of breathing. Your body handles it for you. You feel shortness of breath when there’s an imbalance between the brain’s demand to breathe and the body’s ability to breathe.

How serious is Shortness of Breath?

In a healthy person, shortness of breath can be caused by:

  • Very strenuous exercise
  • Extreme temperatures
  • Bad air quality
  • Obesity
  • High altitude
  • Choking
  • Carbon monoxide poisoning
  • Allergic reaction (for example, following a bee sting)

If you have unexplained shortness of breath, especially if it comes on suddenly and is severe, see a doctor as soon as possible. Breathlessness may be more serious if  it’s accompanied by:

  • Chest pain or pressure
  • Fainting
  • Nausea

Major Respiratory Diseases That Cause Shortness of Breath

Major Non-Respiratory Diseases That Cause Shortness of Breath

Putting It All Together

You just learned a lot about shortness of breath, and you may be confused by everything you just read. The following 5-minute video puts it all together so that you have a comprehensive understanding of shortness of breath in order to receive optimal treatment.

Understanding Shortness of Breath: A Summary


U.S. National Library of Medicine. Cardiovascular System: MeSH Descriptor Data 2021. National Library of Medicine; 2021. Updated February 28, 2018. https://meshb.nlm.nih.gov/record/ui?name=Cardiovascular%20System

Why Am I Short of Breath? – Donald A Mahler, MD. YouTube page. October 2, 2020. https://www.youtube.com/watch?v=Hx–Gf7hrqs&feature=emb_title

Ashton R, Raman D. Dyspnea. Cleveland Clinic. 2015. Accessed June 30, 2020. http://www.clevelandclinicmeded.com/medicalpubs/diseasemanagement/pulmonary/dyspnea/

Symptoms of Shortness of Breath (Alarm Symptoms)

Some people with breathing problems can feel breathless just by doing normal activities like standing up or walking to another room. See your health care provider if you have shortness of breath, especially if it comes on suddenly or is severe.

Other symptoms that may suggest a serious problem include:

  • High fever, chills, and cough
  • Acute shortness of breath with/without chest pain
  • Swelling in your feet and ankles
  • Trouble breathing when you lie flat
  • Lips or fingertips turning blue
  • Associated with swelling of your tongue with hoarseness or trouble swallowing
  • Wheezing, a whistling-type sound when you breathe in or out
  • A high-pitched noise when you breathe
  • Worsening shortness of breath after using an inhaler
  • Breathlessness that doesn’t get better after 30 minutes of rest

What are the risk factors for Shortness of Breath?

Common risk factors include:

  • Being out of shape from lack of exercise or illness
  • High altitudes (mountain sickness)
  • Muscle weakness
  • Low hemoglobin
  • Being out of shape from lack of exercise or illness

Serious risk factors include:

  • Severe obesity
  • Continued exposure to asthma triggers, such as cat dander or ragweed
  • Smoking
  • Prior lung diseases
  • Underlying lung diseases (COPD, asthma, interstitial lung disease)
  • Heart disease (high blood pressure, diabetes, congestive heart failure [CHF])
  • Severe obesity
  • Continued exposure to asthma triggers, such as cat dander or ragweed
  • Smoking or vaping
  • Blood clots that can travel to the lung (DVT, pulmonary emboli)
  • Fluid build-up preventing normal lung function (ascites – fluid in the abdomen, pleural effusion – fluid around the outside of the lungs)
  • High blood pressure in the lung vessels (pulmonary hypertension)

Shortness of Breath vs Normal Breathing

Shortness of breath occurs when your body’s ability to breathe doesn’t match the brain’s orders to breathe. Ordinarily, your airway, lungs, breathing muscles, heart, and blood vessels work together with the brain to maintain sufficient oxygen levels in the body.

Sometimes there’s an imbalance between the brain’s signals to breathe and the ability to breathe. The brain orders the breathing muscles to work harder, and you feel shortness of breath.
1. In a normal state, the pulmonary and cardiovascular organs play a role in maintaining stable levels of oxygen and carbon dioxide.
2. The carotid body is a nerve bundle in the artery in the neck. It monitors oxygen and carbon dioxide levels and communicates the information to the brain.
3. The respiratory muscles, diaphragm, and chest wall work together to let air in and out.
4. The breathing muscles contract, which lets the lungs expand and inhale air. An open airway allows the air to flow smoothly in and out of the lungs.
5. Alveoli in the lungs exchange oxygen and carbon dioxide.
6. The heart pumps blood to the body. Red blood cells in the blood carry oxygen to the body. Blood with less oxygen returns to the lungs.
7. Nerves and receptors in the body send signals to the brain that the organs are functioning properly. The brain regulates the organs so they continue working properly.

Diagnosing Shortness of Breath

Prompt diagnosis is important so that you can begin to manage the cause and symptoms of your shortness of breath. A medical history and exam can often give your health care provider a good explanation. Sometimes, special tests are required.

How is Shortness of Breath diagnosed?

Your doctor or other health care provider will ask you about your symptoms. Try to give him or her as much information about your symptoms as you can.

Your provider will listen to your heart and lungs with a stethoscope. He or she may order additional tests, which could include:

When should you see your health care provider?

Visit your health care provider when a normal activity causes unexpected shortness of breath. Get your breathing difficulty checked if it:

  • Comes on suddenly
  • Is persistent
  • Interferes with your daily activities

It’s important that you contact your health care provider if your shortness of breath doesn’t get better with treatment or is combined with other symptoms, such as chest pain. In such a case, you may need to seek emergency care.

Treating Shortness of Breath

Treatment for shortness of breath depends on its cause. If the cause is your lungs or airways, your health care provider may give you medication. If it’s because of anemia, you may need iron supplements. Most people begin to feel better after the diagnosis is clear. Your provider may recommend that you:

  • Avoid asthma triggers
  • Stop smoking
  • Use oxygen
  • Take part in a pulmonary rehabilitation program

Living with Shortness of Breath

Shortness of breath can usually be managed with:

Other things you can do to prevent and control shortness of breath include:

  • Pacing yourself
  • Trying to not hold your breath
  • Sitting in front of a fan so that it blows on your face.
  • Losing weight if you are overweight
  • Avoiding strenuous activity at elevations above 5000 feet unless you’ve trained in a high-altitude environment
  • Avoiding asthma triggers
  • Avoiding exposure to pollutants in the air, both indoors and outdoors
  • Quitting smoking, even if you’ve smoked for a long time
  • Getting a routine health checkup
  • Continuing medications as prescribed
  • Ensuring that your oxygen supply is adequate and your equipment works properly, if you rely on supplemental oxygen


Questions to ask your health care provider

Set up a meeting with your provider. Together, you can go over how to manage your shortness of breath. See if you qualify for specific treatment, like pulmonary rehab.

When you see your provider, ask:

  • Am I breathless because of my age?
  • What if I stop smoking?
  • How can I reduce indoor air pollutants?
  • How can I exercise if I use oxygen?
  • Why do I get shorter of breath when it’s cold outside?
  • How can I control my asthma?
  • Are my lungs the cause of my shortness of breath, or are there other causes?

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