Shortness of breath is the uncomfortable sensation of not getting enough air to breathe. This may occur when walking, climbing stairs, running or even when sitting still. It can come on suddenly or slowly over weeks to months.

Key Facts

  • If your breathing has become labored and difficult for no obvious reason, it may be the sign of a more serious medical problem.
  • If chest pain or pressure, fainting or nausea accompanies shortness of breath, you should treat it as a medical emergency.
  • Most shortness of breath is manageable with appropriate medication, breathing techniques and exercise.

What Causes Shortness of Breath?

It is normal for things such as strenuous exercise, extreme temperature change, bad air quality, high altitude and obesity to make breathing difficult even for a healthy person. But if your breathing has changed suddenly for no obvious reason, or is getting slowly worse over time, it may be a sign of a more serious problem. Getting older does not by itself cause shortness of breath.

When sudden breathlessness occurs, a number of things could be the cause, which is why you should consult your doctor immediately. For example, an upper airway obstruction, such as a piece of food stuck in your throat, could block your breathing. Some other possible causes include:

  • Carbon monoxide poisoning
  • Heart attack
  • Low blood pressure
  • Asthma flare-up
  • Pneumonia
  • Pulmonary embolism (blood clot in the lungs)
  • Emotional distress or a panic attack

If your shortness of breath symptoms last for four weeks or longer they may be considered chronic. Many conditions can cause chronic breathlessness including:

Page last updated: April 17, 2024

Lung Cancer Biomarker Testing
, | Nov 16, 2024