A wheezing cough can be annoying, and in some cases it may indicate an underlying lung illness. The wheezing sound is created by an obstruction of the oxygen flow leaving the lungs and partially blocked by either excess sputum, or phlegm, or a constricted airway. Conditions such as asthma, bronchitis, chronic obstructive pulmonary disease, heart failure and pulmonary edema may cause a wheezing cough.
According to the American Lung Association, 23 million Americans suffer from asthma. A wheezing cough is the product of the narrowing of the trachea during an asthmatic spasm. In children and young adults, the wheezing cough can lie dormant, then be stimulated by exercise, poor air quality or illness. However, over time, asthmatic tracheas develop scar tissue and are permanently constricted in certain areas. Even a slight cold or illness can trigger a wheezing cough once this occurs.
Bronchitis and Pneumonia
Illnesses of the lungs caused by bacteria or viral invasions cause excessive sputum and trigger airway narrowing. A wheezing cough is a common symptom in acute cases of bronchitis and pneumonia. The wheeze in bronchitis is typically elicited by constriction of the airways, whereas in pneumonia, the wheeze is the product of both constriction and excessive lung secretions. A physician can distinguish the type and severity of a lung illness, as the wheezing cough alone is not indicative of the degree of infection.
Chronic Obstructive Pulmonary Disease
Also known as COPD, chronic obstructive pulmonary disease--including chronic bronchitis and emphysema -- is the fourth leading killer of Americans, according to the American Lung Association. COPD is characterized by a chronic cough, shortness of breath and increased sputum production eliciting the wheezing noise during a cough.
Heart Failure and Pulmonary Edema
Both heart failure and pulmonary edema can elicit a wheezing cough. During heart failure, the heart cannot handle the workload of pumping blood through the body and lungs, allowing fluids to gather within the lungs. This increased fluid stimulates tracheal constriction and leads to a wheeze with breathing or coughing. Pulmonary edema is the condition where the lungs fill with fluid, causing difficulty breathing and a wheezing, non-productive cough. Pulmonary edema is an acute illness that requires emergency medical treatment.