A constant cough is usually considered to be a condition that lasts for more than a few weeks, and can be caused by acid reflux, smoking, asthma, lung diseases, and certain types of lung cancer. Sometimes developing a minor illness such as the common cold or influenza may exacerbate these conditions and lead to a constant cough. Other times, the cough develops over time and becomes more prominent as time goes on.
The causes of a constant cough generally all have one thing in common. They all involve something blocking the airways in the lungs, resulting in coughing, which is the human body’s way of trying to remove the blockage. Most causes of cough are temporary, such as chest congestion due to a cold or brief inhalation of smoke. A constant cough is usually caused by a more serious condition, such as large amounts of tar or mucus in the lungs or a aspiration.
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One cause of a constant cough is smoking. This is commonly referred to as “smoker’s cough” and is caused by tar and mucosal buildup in the lungs. As long as the person continues smoking, consistent coughing may continue throughout his or her life. If he or she manages to quit, oftentimes the lungs can regenerate themselves and cough may subside from several months to a few years after quitting.
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Certain medical conditions, such as asthma, may also cause a constant cough. Lung disease is another possibility, as well as certain types of cancer. In fact, chronic and severe cough is one of the primary symptoms of lung cancer. It may be accompanied by chest pain and wheezing, although sometimes there are no symptoms present at the time of diagnosis.
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Reflux or aspiration of food into the lungs may also cause a constant cough. Sometimes this can be treated with diet and medication, and the cough may subside. Other times surgery may be needed, or food and drink may need to be thickened to keep it from coming back up and into the airways.
Any time a cough lasts more than a week or two, primarily if it is severe and accompanied by mucus or chest pain, a doctor should be consulted to rule out a serious medical condition. Many times there is a simple explanation, such as lingering allergies due to the environment. In some rare cases, a potentially life-threatening illness may be to blame, and treatment will need to begin quickly.