Wheezing manifests as a whistling sound in the lungs while breathing. According to the Mayo Clinic, wheezing is most often heard during exhalation, when the breath is exhaled. Wheezing occurs when the airways that bring air to the lungs become narrow. Because it is associated with narrow airways, wheezing is also usually associated with difficulty breathing. MedlinePlus reports that wheezing is most often caused by narrowing of the smaller airways, called bronchioles. Wheezing is a symptom of multiple different types of diseases.
Asthma
The most common lung disease associated with wheezing is asthma, according to the Mayo Clinic. The Centers for Disease Control and Prevention (CDC) describes asthma as repeated episodes of wheezing accompanied by chest tightness, coughing or difficulty breathing.
The substances that trigger or cause asthma include particles that induce an allergic reaction (such as pet dander or dust), or particles that irritate the lung (such as tobacco smoke or certain chemicals). The CDC describes the treatment of people with asthma as being medications that reduce inflammation and open the airways, as well as prevent exposure to triggering substances.
Chronic Obstructive Pulmonary Disease
Wheezing is also a symptom of chronic obstructive pulmonary disease (COPD). The airways and air sacs of the lungs are elastic and expand and contract easily in the lungs of healthy people. MedlinePlus describes that, in COPD, the airways and air sacs become stretched out and no longer expand and contract normally, making it difficult to breathe. The Mayo Clinic describes COPD as one disease in which wheezing is a possible symptom.
Other Diseases
The Merck Manuals report that the most common diseases that result in wheezing are COPD and asthma. The Mayo Clinic provides a list of the less common diseases associated with wheezing, which include bronchitis, epiglottis (swelling of the top of the wind pipe), heart failure, lung cancer, pneumonia, sleep apnea, respiratory tract infection, smoking and problems with the vocal cords.
