A cough is your body's response to irritation, obstruction or compression of your airways. A chronic cough can be associated with any number of conditions. If you are a smoker, you may have chronic bronchitis, which is characterized by a productive cough that develops over several months or years. Postnasal drip, gastroesophageal reflux disease, asthma, allergic disorders, medications such as ACE inhibitors, infections such as tuberculosis or even cancer can cause chronic cough. Although herbal remedies have not been shown to cure chronic coughs, many people use them. Talk to your doctor before trying to treat a chronic cough with herbs.
Emollients and Expectorants
Mucous that is retained in your airways stimulates receptors that trigger a cough. Normally, this mucous is cleared away by the activity of cilia, which are hair-like projections on the cells that line your upper respiratory tract. These cilia beat in a coordinated fashion to move mucous upward toward your throat, where it is swallowed. Emollients and expectorants loosen mucous or increase the activity of cilia. Mullein, marshmallow root, elecampane, slippery elm bark, fritillaria, lungwort and osha are popular herbal expectorants and emollients, although they have not been approved for the treatment of cough.
Antitussives
Your airways are lined with receptors that are sensitive to chemical irritation, stretching, compression and contact with foreign bodies. When these receptors are stimulated, they send messages to the brain and spinal cord which trigger the convulsive muscular spasm that is a cough. Medications and herbs that suppress the cough reflex are called antitussives. According to Phyllis Balch, author of "Prescription for Herbal Healing," peppermint effectively suppresses the cough reflex. The "Physicians' Desk Reference for Herbal Medicines" lists wild cherry as an antitussive. Ephedra relieves bronchospasm and decreases the cough reflex, but its availability in the United States is limited. None of these herbal preparations has been unequivocally proved to suppress cough.
Anti-inflammatories
Inflammation in your airways can initiate or perpetuate a cough. Inflammation can arise from allergies, asthma, smoking, occupational exposure to noxious fumes or aspiration of acid from your stomach, which often occurs in gastroesophageal reflux disease, or GERD. Licorice root, osha and Siberian and American ginseng are reputed to exert anti-inflammatory activity, but none has been scientifically proved to reduce airway inflammation.
Precautions
A chronic cough is almost always the sign of an underlying medical condition, and some of these can be serious and progressive. If you have a chronic cough, you should see a medical professional to ascertain its cause before you embark on a course of treatment.
References
- "The Merck Manual of Diagnosis and Therapy, 18th Edition: Cough"; Mark H. Beers, M.D., Editor-In-Chief; 2006
- "Prescription for Herbal Healing: Cough"; Phyllis A. Balch, CNC; 2002
- "Physicians' Desk Reference for Herbal Medicines, 2nd Edition: Wild Cherry"; Thomas Fleming, Pharm.D., Chief Editor; 2000
