This is true even if it occurs only in the morning, only at night, or only in the winter. It is also true whether it is a dry cough or a productive cough. A productive cough is one that brings up mucus. A productive cough that lasts for months or comes back year after year is often a sign of chronic bronchitis. Other serious lung infections include pneumonia and tuberculosis.
Allergies are another common cause of a chronic cough.
In some cases, an antihistamine or decongestant drug, bought without a prescription, may decrease allergic coughing. More rarely, a cough can also signal a chronic airway obstruction, asthma, or even cancer. Any cough that causes shortness of breath, severe pain, or brings up blood should prompt immediate medical care. Taking cough drops or syrups for more than a week may only mask the illness while it gets worse. Anyone who has been coughing for a long period of time, should see a healthcare provider for an evaluation.