What is shortness of breath?

People who have shortness of breath describe it in different ways. Some people say that they feel like they can't take a deep
breath in or get enough air. Other people might feel like their chest is tight or they have to work harder than usual to breathe. The medical word for shortness of breath is "dyspnea." Shortness of breath can start suddenly, over minutes to hours. It can also happen over a longer period of time, from weeks to months.

What causes shortness of breath?

Different medical conditions can cause shortness of breath.

Causes of shortness of breath that starts suddenly include:

  • Coronavirus 2019 (COVID-19) – 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. Shortness of Breath
  • A severe allergic reaction, called "anaphylaxis" – This can also cause itching, swelling, or a rash.
  • Pregnancy – It can be normal for pregnant women to feel slightly short of breath just after they lie down or are active.

The most common causes of shortness of breath that happens over weeks to months are:

  • Lung problems, such as asthma or chronic obstructive pulmonary disease (COPD) – Both of these conditions can make it hard to breathe. COPD is usually caused by smoking.
  • 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

Should I see a doctor or nurse?

Yes. If you have shortness of breath, you should see your doctor or nurse.

Sometimes shortness of breath means that your condition is serious and you need emergency help. Call for an ambulance (in the US and Canada, dial 9-1-1) if you have:

  • Shortness of breath and think you are having a heart attack
  • Severe shortness of breath (hard to breathe when you are sitting still)
  • An allergic reaction with shortness of breath

How is shortness of breath treated?

Shortness of breath is treated in different ways, depending on the cause. Once your doctor or nurse figures out the cause of your symptoms, they will talk with you about different possible treatments.