Chronic Cough

When should I be worried about a chronic cough?

Coughing from time to time is normal. It is the body's signal to clear particles from the lung that are trapped in secretions htereby preventing infection and inflammation of the airways. A chronic cough is defined as a cough that lasts longer than eight weeks.

How do I figure out what is causing my chronic cough?

The vast majority of coughs are caused by one of three conditions:

  1. Postnasal drip (mucus streaming down the back of the throat): This may be due to nasal allergies (hay fever) and/or chronic sinusitis and non-allergic rhinitis.The mucus irritates the throat and triggers a cough. Some people may have "silent" postnasal drip and not actually feel the mucus or experience a need to clear the throat.The cough may be worse at night (lying down).
  2. Asthma : Sometimes a dry cough is the only symptom of asthma, a condition caused by inflamed or spastic bronchial tubes. Suspect this if the cough is triggered by laughter, talking, cold air, or exercise. You may also experience chest tightness, wheezing or a feeling of shortness of breath.
  3. Acid reflux (GERD) : This occurs when stomach acids flow back (reflux) into the esophagus and throat and begin to irritate the main airway leading into the lungs (lies next to the esophagus)

Can a specialist help in determining the cause of a chronic cough?

Yes. The allergist will take you through many of the questions posed above at the time of your first visit to assist in narrowing the list of potential triggers. Based upon the findings, a trial of medication may be suggested to see if the cough improves. Lung function tests (such as a breathing test called spirometry) can detect narrowing and reversible spasm of lung airways that may trigger coughing. If sinusitis is the suspected cause and the cough has not improved following appropriate antibiotic and supportive therapy, a CT scan of the sinuses (CAT Scan) might be recommended to help define sinus disease. Allergy skin testing can aid in detecting underlying allergic causes. A diagnosis of GERD is sometimes established by your history coupled with an improvement in the cough when GERD therapy is introduced. We may also collaborate with a gastroenterology specialist for optimal management in severe cases.

How is a chronic cough treated?

First and foremost, the reason for the cough must be determined. Once the allergist is reasonably certain of the cause, targeted treatment can be started. Postnasal drip due to allergies might be treated with some combination of antihistamine/decongestants, nasal steroid sprays, or antihistamine nasal sprays, in addition to the most important "treatment" -- avoidance of exposure to the allergen. If the postnasal drip is the result of a chronic sinus infection, then antibiotics coupled with measures to "clean out" the sinuses may be recommended.

The treatment of cough variant asthma or asthma due to reactivity of the airways will vary according to the underlying triggers and may include inhalers and medications to reduce airway inflammation. If the cough continues despite the above treatment measures, other tests and recommendations for further evaluation may be needed.