Breathing involves the movement of oxygen and carbon dioxide into and out of the body. Adequate intake of oxygen and removal of carbon dioxide is important to maintain body function.

Physical, environmental, psychological, and social factors can contribute to the feeling of breathlessness.

Common causes include:

• Lung conditions such as asthma, chronic obstructive pulmonary disease, interstitial lung disease, pneumonia
• Heart conditions such as heart failure
• Psychological conditions such as anxiety