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A cough is the body’s natural reflex that helps clear the airways of foreign particles and irritants.
“The whole purpose of the cough is to help clear the lungs of mucus, infection, or anything that develops in the lungs,” says Nicholas Roy, DO, an expert in internal medicine, pulmonary medicine, and critical care in Vineland, New Jersey.
A common cause of persistent cough is postnasal drip, in which mucus drips down the throat and triggers a cough. Allergens are another common irritant. When these cause you to cough, you don’t likely need to worry. When a cough becomes chronic (persistent and ongoing), however, it may be a sign of a more serious health concern.
Sources: Harvard Health Publishing. That Nagging ... + 20
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