Wheezing is a high-pitched whistling sound that occurs during breathing when air moves through narrowed breathing tubes in the lungs. It can be a sign of an underlying health issue, so its important to know when wheezing needs to be evaluated. The most common causes of wheezing include:

• Asthma: This condition, in which your airways narrow, swell, and make extra mucus, can make it hard to breathe.

• Chronic obstructive pulmonary disease (COPD): This is a group of lung diseases that make it difficult to breathe and get worse over time.

• Bronchitis: This is an inflammation of the lining of the bronchial tubes, which carry air to and from the lungs.

• Pneumonia: This is an infection that inflames the air sacs in one or both lungs, which may cause wheezing.

• Allergic reactions: Allergies to pollen, chemicals, pet dander, dust, foods, or insect stings can cause wheezing.

• Vocal cord problems: Certain vocal cord problems can cause wheezing.

• Smoking: Smoking can cause wheezing, and people with emphysema or heart failure are more likely to have wheezing.

• Viral infections: Viral infections, especially in infants younger than age 2, can cause wheezing.

Wheezing can also be caused by other less common conditions, such as the lodging of a foreign object in the airway, cystic fibrosis, gastroesophageal reflux disease (GERD), sleep apnea, or a tumor in the airway. If wheezing occurs for the first time, keeps occurring without explanation, or is accompanied by significant shortness of breath, bluish skin, confusion, or mental status changes, its important to contact a medical professional.