Remember that the nose and lungs are intimately connected, so an infection or inflammation that occurs in the nose can travel to the lungs, causing a host of significant conditions. Infected mucus can enter the lower airways through the trachea and the bronchi, leading to tracheitis and/or bronchitis. These conditions will manifest themselves in a range of symptoms, from a dry, heaving cough to difficulty breathing with a tightness of the chest.
When the smaller airways of the lung (alveoli) become involved, you may experience asthma symptoms. These symptoms range from mild wheezing to severe tightness or constriction of the chest, with severe shortness of breath. This reaction occurs when the lung tightens up so much that air cannot enter the lungs, and breathing can potentially stop. This is called status asthmaticus. Without treatment, asthma can be fatal. However, with the proper medication, asthma is completely controllable. If you or someone you know is suffering from tightness in the chest or persistent wheezing or coughing, please seek medical help right away.
When the lung tissue itself becomes infected and full of mucus that cannot be cleared through coughing, you may have developed pneumonia. In this instance, the infection actually invades the deep tissues of the lungs. The symptoms of pneumonia range from a persistent, ineffective cough to severe shortness of breath, and must be treated with prescription medication, which will clear the infection. Without proper treatment, pneumonia can also be fatal.