Did you know that when a person coughs, air may move through the trachea at a speed of more than 480 KPH? The cough reflex is a natural physiological response to irritation. It is an important defense mechanism that plays a major role in maintaining the integrity of the airways and can be voluntary or involuntary.
Coughing is commonly triggered by mechanical or chemical stimulation of receptors in the pharynx, larynx, trachea and bronchi. However, cough receptors also exist elsewhere in the body such as in the nose, external auditory ear canals, and even the stomach and diaphragm. On the one hand coughing helps to clear secretions and foreign objects from the respiratory tract/airways, which is good, but on the other hand it can also transmit disease, usually via droplets.
Chronic cough is cited as one of the most common reasons for doctor visits in the USA and other industrialised nations. Coughs are often symptomatic of conditions ranging from the common cold and postnasal drip (PND) to life-threatening diseases, e.g. emphysema, pulmonary oedema and malignancies like lung cancer. In South Africa, and the Western Cape in particular, we also have rampant tuberculosis (TB).
Types of cough can be subdivided simply into acute or chronic, and wet or dry, i.e. productive or non-productive, daytime and/or nocturnal, postprandial or occurring with meals. Dry coughs and wet coughs, in turn, have a variety of manifestations. In addition, coughs may occur on waking, or on consumption of certain foods like milk products or citrus, etc.
Acute coughs are generally characterised by lasting less than 3 weeks, subacute coughs may last between 3 and 8 weeks, whereas chronic coughs persist for more than 8 weeks.
Coughs are often described quite creatively as paroxysmal, barking (may be indicative of croup or bronchitis), honking, wheezing (common in asthma and bronchitis), hacking, raspy, tickly, irritating, etc. but whatever the description, incessant coughing can rob people of sleep, and cause urinary incontinence and chest pain, impacting on work and lifestyle, besides generally interfering with quality of life.
The coughs of viral infections are at first dry and spasmodic, but small amounts of white, thick sputum are usually produced as they progress. This type of cough can either be relieved with cough suppressants or made productive by using expectorants. Acute dry coughs may also be due to inhaled irritants, or allergies. Chronic dry coughs are often classified as non-infective (TB excluded), and are usually due to more serious conditions such as fibrosis or congestive heart failure.
When respiratory infections are present the sputum generally becomes thicker and more abundant, with a consequent productive cough. Productive coughs usually occur several days after contracting a bacterial infection, and last for about 1 week. In cases of chronic bronchitis however, these coughs become persistent and re-occur periodically. Chronic wet coughs with clear or coloured (yellow, green-brown) sputum are most likely due to a longstanding irritation such as from smoking. Generally, yellow-coloured sputum indicates pus, which is indicative of a secondary bacterial infection. Since productive coughs are a necessary means of removing infectious and obstructive material from the airways, cough suppressants (antitussives) should be reserved for dry coughs, unless the cough is completely exhausting the person or preventing sleep.
Fundamentally, innate health status, lifestyle and environmental conditions all play a vital role in the development and consequential conditions related to coughs.
CAUSES OF CHRONIC COUGH
The most common cause of chronic cough in adults is smoking. Apart from this, most other coughs appear to be due to acute upper respiratory tract viral infections. Postnasal drip (PND), alone or in association with some other condition, is the most common cause of chronic cough in non-smoking, immunocompetent adults, followed by asthma, and gastrooesophageal reflux disease (GORD). Other causes of chronic cough may be due to iron deficiency (particularly in some women), or bronchiectasis (an abnormal stretching and enlarging of parts of the respiratory system’s bronchial tree, as a result of mucus blockage).
A study found that between 70% and 90% of patients with lung cancer develop cough at some time during the course of the disease, but isolated chronic cough is an infrequent presentation of lung cancer. Other signs and symptoms of cancer are usually present in these patients by the time cough appears. A change in the pattern of a smoker’s cough may however herald associated complications such as bronchogenic neoplasm.
Certain medications known as ACE inhibitors can cause a chronic, non-productive cough. Beta blockers and aspirin may also cause coughing as a side-effect.
Chronic coughs in children are usually due to infections, including sinus infections, pneumonia, allergies, asthma, and reflux. A chronic cough that is worse at night may indicate reflux. Researchers Haber et al. also include sinusitis, TB, whooping cough (pertussis) and cystic fibrosis as potential causes of chronic cough in children. Recurrent infections in children may also be an indication of an underlying immunological disorder as the cause of cough. Something practical that should not to be overlooked is the possibility of foreign body aspiration in young children.
CAUSES OF ACUTE COUGH
Research published in the New England Journal of Medicine concludes that the most common cause of acute coughs is viral upper respiratory tract infections (URTIs) such as the common cold and acute bacterial sinusitis. Viral URTIs are usually self-limiting – so rushing off for antibiotic treatment is not the smartest thing to do, as antibiotics cannot kill viruses, only bacteria. Allergic and/or non-allergic rhinitis, whooping cough, pneumonia, environmental exposure, and chronic obstructive pulmonary disease (COPD) exacerbations, such as emphysema or chronic bronchitis, as well as pathogenic fungi, may however be other causative factors. There are other causes of bronchitis including certain bacterial infections as well as environmental irritants like cigarette smoke, pollution, dust, and chemical fumes. Some people are more at risk of developing bronchitis than others, e.g. the elderly, people with a lowered immune system, those who are continuously exposed to lung irritants, and people working in certain occupational settings. Avoidance of smoking can therefore act as one of the most significant natural cures for bronchitis, since prevention can be the greatest deterrent for perpetuation of this illness.
Acute coughs in children may be due to croup, a common childhood viral ailment that typically affects children between the ages of six months and three years. Croup usually manifests with an abrupt onset of symptoms, in the middle of the night. Symptoms include a very distinctive, brassy cough, often accompanied by a loud, high-pitched sound when breathing in. Croup symptoms tend to improve during the day, but worsen again at night or when the child becomes agitated.
Subacute coughs are cited as generally being due to bacterial sinusitis, URTI and asthma. Acute coughs are therefore relatively easy to identify or diagnose, and treat, compared with chronic coughs, which tend to be more multi-causal. Some coughs may morph from an acute cough into a chronic cough. These coughs have been termed ‘100 day coughs’, and can be fairly resistant to treatment and very stressful and debilitating.
Collectively, research findings conclude that the most common causes of coughs in adults are due to postnasal drip syndrome, asthma, GORD, bronchitis, certain drugs, smoking and other irritants, and post-infectious bronchial inflammation. Whereas in children upper and lower respiratory tract infections, asthma and GORD are reported to be the most common causes of coughs.
The treatment of cough is determined by the cause. Coughs are conventionally treated with cough-suppressant medicines (antitussives), drugs that dry out catarrhal secretions (antihistamines and decongestants), and those that dilate the airways (bronchodilators). Codeine is a popular and frequently prescribed cough suppressant, but since it also dries the respiratory mucosa, narrows the respiratory tubes, and is a mild respiratory depressant, it can aggravate some respiratory conditions. Other side-effects of codeine include nausea, vomiting, and constipation.
Using medication to suppress the body’s urge to cough is less than ideal, as the body usually wants to expel mucus and irritants by way of a cough. A much healthier option would be to use natural herbal agents, including aromatherapy essential oils, to help liquefy and expel mucus (mucolytics and expectorants), open the airways (bronchodilators and decongestants), modulate coughing (spasmolytics), soothe inflammation and pain (anti-inflammatories, balsamics, demulcents and anodynes), combat infection (eubiotics) if needed, and boost immunity. Natural antitussives are also available if and when indicated. There are also some excellent homeopathic remedies for treating coughs.
Remember that adequate hydration is an important component of natural treatment – our cells need lots of it for optimal functioning. So drink plenty of pure water, as well as healing herbal teas that are respiratory system specific. Water can play an additional role in treating coughs in the form of steam inhalations and aromatic vaporisations, which very effectively assist in soothing and reducing symptoms of respiratory irritation. Ravintsara (Cinnamomum camphora CT cineole) and Eucalyptus radiata are two of the all-round best essential oils to have on hand for treating many of the symptoms of coughs, whether treating them through inhalations or topically.
A healthy, natural and unprocessed diet, rich in vitamins, minerals, bioflavonoids, herbs and spices, is the cornerstone of good health – not only for the respiratory system, but for every other body system too.
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