It can be caused by many conditions, but asthma and chronic obstructive pulmonary disease are the most common. These cause a narrowing of, and/or spasms in, the small airways of your lungs. Other common ailments associated with wheezing include allergic reactions or a physical obstruction, such as a tumor.
People who have hay fever may often struggle to breathe normally and suffer from bouts of wheezing. Wheezing may be related to respiratory infections like acute bronchitis. People with heart conditions may also have difficulty breathing and find themselves wheezing.
Asthma, which is becoming more common globally due largely to urban air pollution, is a primary cause of wheezing. Asthma is an inflammation causing airways to narrow and can trigger muscle spasms in the wall of the airways. If you suffer from hay fever or other allergies try to avoid the triggers that make you wheeze.
The list of possible causes of wheezing is long and includes congestive heart failure, and pneumonia. Bronchitis, epiglottis (a swelling on the windpipe) and sleep apnea, (stop-start breathing during sleep) are other possible causes.