Diseases affecting the lower airway, such as asthma asthma
Asthma is a common chronic inflammatory airway disease, characterized by variable and recurring symptoms, reversible airflow obstruction and bronchospasm.
, bronchitis bronchitis
Bronchitis is an inflammation of the bronchi, the larger and medium-sized air passages of the lung.
, pneumonia pneumonia
Pneumonia is an inflammatory condition of the lung.
or chronic obstructive obstructive
Increased resistance in the airways that reduces the amount of air inhaled in each breath and the oxygen that reaches the pulmonary arteries
pulmonary disease COPD (commonly known as "smokers' cough") are counted amongst the most common diseases.

See below for the most common clinical pictures: