The Smoker's Cough
Smokers often suffer cough. Parental smoking is also a major cause of cough in children.6
Two types of cells line the inner lumen of the respiratory tract: ciliary cells and goblet cells. The goblet cells produce a majority of the mucus that acts to entrap inhaled pollutants, carcinogens, bacteria, and viruses. Ciliated cells act via millions of constantly moving cilia to move the mucus and entrapped foreign material upward so the person may swallow or expectorate it. Thus, this process of mucokinesis protects the healthy individual against such problems as pulmonary carcinoma, the common cold, and influenza.
Normally, the mucus is of sufficiently low viscosity that it is easily moved upward by ciliated cells. Smoking increases the volume of mucus produced in the lungs, and increases its viscosity. Smoking also decreases the activity of the ciliated cells. The pulmonary system must remove increased quantities of abnormally thickened mucus containing entrapped carcinogens, but this is simply not possible in the face of a clinically impaired muco-ciliary defense system. The result is chronic bronchitis. While some smokers have a dry, hacking cough, others report a productive cough. The productive smoker's cough is vital to supplement the impaired cilia, and must not be suppressed. This is the reason that self-treatment of cough by smokers must be prohibited.
Infective Cough
Patients are cautioned not to self-treat cough if excessive mucus is present. Bronchial or sinus infection may cause the patient to develop a cough that produces sputum. The bacteria (often Haemophilus influenzae, Streptococcus pneumoniae, branhamella, or moraxella) cause the sputum to have a yellowish or greenish color.4,7 Hence, excessive sputum--especially discolored sputum--requires a physician visit.
GERD-Induced Cough
Gastroesophageal reflux disease is an under-diagnosed cause of chronic cough.8 It causes 10% to 21% of chronic coughs.3 Its etiology is most often due to serial distal esophageal stimulation, though the patient might occasionally experience cough secondary to tracheal aspiration. An unfortunate fact is that most patients with GERD-induced cough do not experience additional GERD symptoms because reflux is confined to the distal esophagus and does not reach the pharynx.5 Thus, cough in these patients may be treated as an isolated complaint, while the unrecognized GERD continues to damage the esophagus and stimulate additional coughing. GERD-associated cough may be positively identified when anti-reflux medications help the problem, or when esophageal pH testing uncovers clear acidic changes consistent with reflux episodes.2,4
Postnasal Drip
The most common cause of chronic dry cough is a combination of postnasal drip, chronic rhinitis and sinusitis.5 The patient with postnasal drip-induced cough will complain of secretions in the back of the throat coupled with a frequent need to clear the throat, as well as ancillary symptoms such as sneezing and nasal congestion.2,4,5 If congestion is profound, the patient will speak with a nasal voice. Cough may be a direct result of upper airway inflammation, or it may result from secretion-induced stimulation of laryngeal cough receptors.2,4 Topical corticosteroids combined with anti histamines may be helpful; premedication with topical nasal decongestants can enhance sinus penetration.
Treatment of Cough
Ingredients that are safe and effective for productive cough include guaifenesin. Nonproductive coughs may be safely treated with dextromethorphan, camphor/menthol ointments or steam inhalants, oral menthol (in lozenges, etc.), or codeine (but only in states that allow sales of codeine as a Schedule V substance).
PATIENT INFORMATION: HOW TO TREAT YOUR COUGH
Cough is a common symptom in patients of virtually all ages. The severity of cough ranges from a mild, barely noticeable, quiet cough to loud, rattling coughs that are accompanied by barking sounds. Many people cough once or twice during the day. These coughs are usually harmless attempts to clear the airways, and need not be treated. However, airway clearance can be facilitated by drinking 8 to 10 eight-ounce glasses of water daily.
Cough of the Common Cold: Almost everyone has had a common cold and can recognize its presence. In most cases, it begins with a scratchy or painful throat, followed by nasal congestion and runny nose, and the development of a cough. At first, the cough may help you raise thick secretions in the lungs to prevent pneumonia. These "productive" coughs are beneficial, and should not be stopped. Instead, you should drink lots of water, use a vaporizer or a humidifier, and take a nonprescription product containing guaifenes-in, such as Robitussin.
However, there are times when all other cold symptoms have disappeared, but a cough hangs on for several days. This dry, hacking, nonproductive cough can be halted with the use of such nonprescription ingredients as dextromethorphan (Vicks 44), topical menthol products (Vicks Vaporub, Mentholatum), menthol lozenges or tablets (Hall's), or vaporizer inhalants (Kaz Inhalant, Vicks Inhalant).
If the cough is productive but disrupts sleep, a product containing guaifenesin and dextromethorphan may be the best choice (e.g., Vicks 44-D, Robitussin DM).
When to See a Physician: There are times when a person with cough should have a professional checkup. For instance, cough in those under the age of 2 years should be evaluated by the pediatrician. Any time cough lasts longer than 7 days or recurs, a more serious underlying condition such as cystic fibrosis could be present, and a physician must be seen.
If a cough is not accompanied by runny nose or sore throat, it may not be due to a common cold at all. Some patients already suspect that the cough is caused by another problem. If it is due to smoking, asthma, or is accompanied by excess phlegm, a physician appointment should be made. You may recall a specific event, such as use of a chemical or solvent in a closed place, that preceded the airway irritation. You may have experienced lung damage from the chemical, and a check-up is a wise idea. Certain blood pressure medications ("ACE-inhibitors") can cause a chronic dry cough. If you suspect your cough is a side effect of medication, Consult Your Pharmacist. These vital beneficial medications should not be discontinued without your physician's approval.
You may experience episodes of gastroesophageal reflux, in which stomach contents travel up into the esophagus. As they damage the esophageal tissues, they can also damage some of the airway tissues and produce a cough. You may choose to try several lifestyle modifications, along with such nonprescription products as Gaviscon, Pepcid AC, Zantac 75, Axid AR, or Tagamet HB 200.
Remember, if you have questions, Consult Your Pharmacist.