A persistent cough can disrupt your life, make it difficult to sleep, and put a wrench in your relationships. When you can't stop coughing, it is not only annoying, it also drains your energy and disturbs your quality of life.

Possible Causes

A cough begins when an irritant such as perfume, dust, or even spicy food, stimulates nerves in your respiratory tract. A cough helps clear foreign substances and secretions from your lungs and prevents infection. However, when a cough persists for a long period of time, it is usually the result of an underlying problem. Here are some possibilities:

  • Air pollution. Various pollutants and irritants in the air can cause a persistent cough.
  • Asthma. Coughing is a characteristic symptom of asthma, one that tends to intensify at night or in the early morning. An asthma-related cough may come and go with the seasons, appear after an upper respiratory tract infection, or become worse when you're exposed to cold air or certain chemicals or fragrances.
  • Blood pressure drugs. ACE inhibitors are known to cause chronic cough in about 20 percent of the people taking them.
  • Chronic bronchitis. This long-term inflammation of your bronchial tubes can cause congestion, breathlessness, wheezing, and a cough that brings up discolored mucus.
  • Chronic Obstructive Pulmonary Disease (COPD). With COPD, the lungs produce excess mucus, which the body reflexively tries to clear by coughing.
  • Gastronesophageal Reflux Syndrome (GERD). GERD is an ailment of the stomach and esophagus that occurs when stomach acid backs up into the esophagus due to a weak valve. The constant irritation in your esophagus, throa,t and even your lungs can lead to chronic coughing.
  • Mold. Mold spores in homes and office buildings can cause wheezing and coughing when inhaled.
  • Post-nasal drip. When you have more mucus than usual--from allergies, a cold or sinus infection--you may feel it accumulating in the back of your throat. This excess mucus, called postnasal drip, can cause irritation and inflammation that triggers your cough reflex. If the postnasal drip is chronic, your cough is likely to become chronic too.
  • Respiratory tract infection. A cough can linger long after most symptoms of a cold, flu, pneumonia, or other infection of the upper respiratory tract have gone away. In some cases, this may occur because the infection is lingering. Sometimes, even if the infection is gone, your airways may remain inflamed and therefore especially sensitive to irritants.

What to Do

If you have been experiencing a chronic cough, you should consult your doctor to investigate and treat possible underlying causes.

To prepare for your appointment, do the following:

  • Make a list with detailed descriptions of your symptoms.
  • Write down detailed information about any medical issues you've had.
  • Make a list of all of the medications and dietary supplements you take.
  • Write a list of questions for your doctor.
  • If you are a smoker, take the appropriate steps to quit. Ask your doctor for recommendations to support you through the process.

Bottom Line

If you have a lingering cough, see your doctor to determine the underlying cause(s) and begin the appropriate treatment.

Sources

"Cough." FamilyDoctor.org. Web. 26 May 2010. http://familydoctor.org/online/famdocen/home/tools/symptom/516.html

"Cough." MedlinePlus. Web. 26 May 2010. http://www.nlm.nih.gov/medlineplus/ency/article/003072.htm

Mayo Clinic Staff. "Chronic Cough." MayoClinic.com. Web. 26 May 2010. http://www.mayoclinic.com/health/chronic-cough/ds00957

"What are the Signs and Symptoms of COPD?" National Heart Lung and Blood Institute. Web. 26 May 2010. http://www.nhlbi.nih.gov/health/dci/Diseases/Copd/Copd_SignsAndSymptoms.html