What Are the Causes of a Dry Cough?

For over a year now I have had problems with a very dry cough with nothing in my lungs or chest. At times, it feels as if I have swallowed dust and I begin to choke and cough. Many times the choking attack happens while I am eating and/or drinking. Sometimes my throat gets very, very dry while I am talking, which spurs an attack of coughing and choking, and it has also happened while I was sleeping. The choking attack feels like I have swallowed something down my windpipe. What could this be?

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This is a surprisingly common problem, one that is both challenging and frustrating. Sadly, it is not uncommon for a patient with dry cough to be seen by a variety of specialists (ear, nose and throat; gastroenterology; pulmonology; allergy; and even psychiatry) and still emerge with no diagnosis and no effective treatment.

Here are a few of the more common explanations for persistant dry cough:

  • Cough-variant asthma. The usual symptoms we associate with asthma -- wheezing, chest tightness, shortness of breath -- are not always present. (Incidentally, a wheeze is a high-pitched sound that occurs during exhalation. Imagine the sound of bagpipes deflating.) In cough-variant asthma, dry cough may be the only symptom of disease.
  • Medications. There is a class of blood-pressure medications known as angiotensin-converting-enzyme (ACE) inhibitors. Chronic, dry cough is a well-known side effect of ACE inhibitors. If your cough began soon after you started taking one of these drugs, you should talk to your doctor about changing to a different class of blood-pressure medication.
  • Gastroesophageal reflux disease (GERD). Our throats were never meant to be exposed to stomach acid and digestive enzymes; only our stomachs can handle this without injury. Contact of acid and digestive enzymes with the vocal cords and windpipe (trachea) will almost always provoke a cough. In most cases of GERD, patients are unconscious of the real problem, since reflux occurs primarily when they are horizontal and unconscious (asleep, in other words!). The aftereffects are experienced during the daytime. These include dry cough, hoarseness (and other voice changes), chronic throat-clearing, esophageal spasm and globus sensation (the "lump in my throat" feeling).
  • Postnasal drainage. Allergies and chronic sinusitis are common causes of postnasal drainage. Postnasal drainage usually, but not always, results in a productive cough. (A wet cough, generating mucus, is known as a productive cough; dry cough is also called a nonproductive cough.) As with GERD, if drainage occurs primarily at night, the patient may not be conscious of the true nature of his or her condition.
  • Other lung diseases. Cough is a common initial symptom of many lung diseases, including tuberculosis, lung cancer, emphysema and pneumoconioses (occupational lung diseases such as miner's lung). Cough from such illnesses may or may not be productive.

Although my opening paragraph may have been discouraging, you should not neglect this problem. Your best chance at effective treatment is to find the causes of your dry cough and treat the problem accordingly. For this, you will need a physician who is patient and diligent. Start with a nonspecialist, such as your internist or family practitioner; hopefully, your doctor will be able to determine if referral to a specialist is necessary. (My soapbox position: If your doctor takes two minutes of history and then writes you a prescription for a cough suppressant, find another doctor.)

 

by Douglas Hoffman

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