Chronic coughing is often defined as a cough that endures longer than three weeks. Chronic coughing in children can have several causes such as reaction to secondhand tobacco smoke, postnasal drip, pneumonia, or bronchitis.

Sometimes asthma can cause chronic coughing — existing without other asthma symptoms such as wheezing or nasal congestion. This is called hidden or cough-variant asthma. Some studies have indicated that between 30 to 50 percent of individuals with a chronic cough may actually have undiagnosed asthma.

The cough may first surface following a cold or upper respiratory tract infection. It could begin as a small “tickle” in your child's throat, and it is nonproductive, meaning that no sputum or mucus is produced with the cough. Other times coughing could be triggered by a variety of activities including laughing, exercise, or even cold weather.

According to the American Academy of Pediatrics, a persistent cough is usually secondary to a condition such as asthma, an allergy, an infection, or environmental irritants such as tobacco smoke or dust. Therefore, therapy should be directed at the underlying condition for the maximum benefit. Also, coughing can be helpful by loosening secretions and clearing them from the airways.

If you see your child coughing, for instance, while playing sports or involved in other strenuous activities, consider an asthma evaluation. A health care provider should be prepared to evaluate any cough that does not stop within three to six weeks.