By Drs. Sally Robinson and Keith Bly

Coughing is the body’s way to clear air passages. It is a symptom of illness, not a disease. Therefore, the illness that is causing your child to have a cough may require treatment.

Coughing can be caused by many things, such as the common cold, inhaling small particles from the air, smoking, asthma, bacterial or viral infections that affect the lungs, or severe illness, such as pneumonia.

Older children and adults can usually tell whether their cough is caused by inhaling dust or smoke particles or by an infection. But when your younger child coughs, you might not be able to tell whether your child is ill or has something in his air passages. If your child has a fever accompanying the cough, then he or she probably has an infection.

Even though coughing is a healthy bodily reflex, several types of coughs may require a visit to your child’s doctor. If you learn to tell the difference between the types of coughs, you will know how to deal with them and will be able to tell if your child needs to see her doctor.

A "barking" cough is usually caused by an inflammation of the larynx (voice box) and trachea (windpipe) known as croup. It is associated with viral upper respiratory infections, allergies or sudden changes in temperature at night. When a young child's airway becomes inflamed, it can swell around the vocal cords, making it harder to breathe. Children younger than 3 years of age get croup most often because their windpipes are narrow. Croup can occur suddenly in the middle of the night, which can be frightening for both you and your child. Although most cases can be managed at home, if you suspect your child has croup, call your child's doctor to determine whether a doctor’s visit is in order.

Whooping cough, or pertussis, is a deadly vaccine-preventable disease. The whooping noise is a symptom of pertussis and occurs after coughing, when the child tries to take a deep breath. Children with pertussis may not get enough oxygen and may even stop breathing. If you think that your child may have pertussis and he has not had the DTP (diphtheria/tetanus/pertussis) vaccination, see a doctor immediately.

When your child makes a wheezing sound when she exhales, it may be a sign that something is blocking the lower airway. This happen if there is swelling from a respiratory infection, asthma or an object stuck in the airway. Call the doctor unless your child is already being treated for asthma and you have medicine to treat it. If coughing and wheezing do not improve with medication, call your child's doctor.

Call a doctor if your child:

• Is coughing up green, rust-colored, yellow, bloody or foul-smelling phlegm
• Has trouble breathing
• Has bluish lips, face or tongue
• Has chest pain
• Is short of breath or wheezing
• Has pain or swelling in her calves
• Has a recurrent night-time cough
• Has sudden weight loss
• Has high fever, especially if your child is an infant.
Dr. Sally Robinson is a pediatrician in the division of children’s special services at the University of Texas Medical Branch at Galveston. She teaches medical students about caring for children with chronic medical conditions. Dr. Keith Bly is a hospitalist and assistant professor of pediatrics at UTMB.

The Your Health column is written by health and medical experts at the University of Texas Medical Branch at Galveston. The column focuses on topical health issues that we believe are of interest to your readers. It is e-mailed every Tuesday. If you have any questions about the column, or would like to suggest topics, please contact John Koloen, media relations specialist, at (409) 772-8790 or email jskoloen@utmb.edu.