What Causes Breathlessness?

Different medical conditions can cause shortness of breath.

Shortness of breath that starts suddenly can be caused by:

  • Coronavirus 2019 – This is an infection caused by a virus called SARS-CoV-2.
  • Lung problems, such as asthma, infections, or blood clots – These conditions might cause other symptoms, too. For example, a lung infection usually causes a fever and cough.
  • Heart problems, such as a heart attack or heart failure – A heart attack can also cause chest pain or pressure. Heart failure is when the heart does not pump as well as it should.
  • A severe allergic reaction, called "anaphylaxis"
  • Pregnancy

For shortness of breath that happens over weeks to months, the most common causes are:

  • Lung problems, such as asthma or chronic obstructive pulmonary disease (COPD) – Both of these conditions can make it hard to breathe. COPD usually happens in people who have smoked for at least several years.
  • Heart problems, such as heart failure or a change in the size and shape of the heart (called cardiomyopathy)
  • Being overweight or out of shape
  • Anxiety or panic disorders

Risk Factors

Controllable

Tobacco and secondhand smoke
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Radon
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Asbestos
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Toxic workplace chemicals
toxic workplace chemicals

Non-controllable

Genetics
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Air pollution
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Radiation therapy
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