Definition

A high-pitched, whistling sound that can occur during breathing when the airways in the lungs become narrowed or blocked. Wheezing is a sign that a person may be having trouble breathing. There are many causes of wheezing, but the most common causes are asthma, chronic obstructive pulmonary disease, bronchitis, and pulmonary edema. Other causes include cystic fibrosis, pneumonia or other respiratory infections, breathing a foreign object into the lungs, congestive heart failure, vocal cord problems, acid reflux disease, allergies, severe allergic reactions, certain medicines, smoking, or a tumor in the lung or airway.