Bronchitis refers to inflammation of the tubes of the airways (bronchi) due to infection, irritation or obstruction. It’s a common cause of cough, which may also be a symptom of other respiratory conditions, including colds, flu, hayfever and sinusitis.
Coughing is a reflexive action that occurs when the body is attempting to clear the airways, usually in response to some form of obstruction, inflammation or irritation. It involves a deep inhalation and subsequent rapid, forced exhalation, which creates the characteristic sound of the cough.
A cough is often described as either ‘wet’ or ‘dry’ depending on whether or not it is accompanied by the production of phlegm (also known as sputum), which can vary in colour and thickness, from clear and watery, to thick and yellow or green.
Bronchitis is typically characterised by a wet (or ‘productive’) cough, with other symptoms varying according to the condition’s cause and duration.
When it’s caused by an infection, additional symptoms of bronchitis may include sore throat, muscle aches and pains, fatigue, headaches and nasal congestion or discharge. In many cases, the cough can linger on after all the other symptoms of respiratory infection have resolved, and in these circumstances, the cough may become dry (or ‘unproductive’) and hacking, without the expulsion of phlegm.
Most cases of acute bronchitis are resolved after around three weeks. Bronchitis that’s more persistent or recurrent (occurring for at least three months of the year over two or more years) is considered chronic, and may worsen over time causing serious breathing problems and other symptoms, including shortness of breath (dyspnoea), and the development of a blue tinge (cyanosis) on the lips, mucous membranes, fingers and toes.
Coughing occurs when something irritates or obstructs the mucous membranes of the airways. Common triggers include infections, post-nasal drip (in which mucus drips into the throat from the nasal passages) and the inhalation of foreign bodies and allergens.
Acute bronchitis is usually due to viral or bacterial infection, while chronic bronchitis is often due to non-infectious causes like cigarette smoking and exposure to environmental contaminants (like chemicals, dust or asbestos).
In both infectious and non-infectious bronchitis, irritation and inflammation of the airways prompts the increased production of sputum, which forms on the membranes lining the affected parts of the respiratory tract making breathing difficult and triggering cough.
When the mucous is particularly thick, sticky or copious, it may become difficult to expel. As it accumulates, it may form a hospitable environment for the growth of bacteria, paving the way for a secondary infection to develop as a complication of an existing viral infection (e.g. colds and flu) or an acute exacerbation of chronic bronchitis.
In traditional Chinese medicine (TCM), the Lung organ-meridian system encompasses not only the lungs themselves, but also the skin and mucous membranes such as the throat and nasal passages. It’s responsible for breathing, immune system function and keeping the body’s various fluids in a liquid state.
According to this philosophy, as we inhale oxygen, we also inhale Qi (energy) from the air, which the Lung organ-meridian system disperses through the body in a downward direction enabling it to be combined with other types of Qi to form the energy that powers human life.
If the dispersal and downward movement of the Lung Qi is impeded, it accumulates and eventually travels upwards instead, resulting in coughing.
Similarly, if the Lung organ-meridian is unable to liquefy the fluids in the lungs appropriately, phlegm may accumulate, leading to bronchial congestion and cough.
If the functioning of the Lung organ-meridian is weak or out of balance, the body’s Defensive Qi (resistance to illness) is likely to be affected too, increasing your susceptibility to disease-causing influences.
In the case of bronchitis and cough, those influences may include not only bacteria and viruses (as per the Western understanding of respiratory infections), but also an excess of Wind, commonly in combination with excess Cold, Heat and/or Dryness.
The Western herbs Elecampane and White Horehound have traditionally been used to relieve bronchial congestion and coughs.
They’re often taken alongside Chinese herbs traditionally used to dissolve and clear phlegm, moisten Dryness and relieve wet and dry coughs, such as Aster, Platycodon and Chinese Licorice.
From the perspective of TCM, these Chinese Lung tonic herbs work by addressing the effects of Wind (including Wind-Cold and Wind-Heat). Aster and Platycodon also promote the downward movement of Lung Qi, while Chinese Licorice provides additional soothing and anti-inflammatory effects on the respiratory mucous membranes.
Herbs traditionally used to relieve coughing due to the bronchial congestion of upper respiratory infections include Elecampane, Aster, Stemona, Chinese Licorice and Thyme Oil.
Experiencing repeated episodes of colds, flu or bronchitis suggests your Defensive Qi is compromised or your immune system is weak.
Chinese herbalists traditionally use immune tonic herbs such as Astragalus, Codonopsis and Ganoderma (Reishi) to enhance Defensive Qi, strengthen resistance against minor infection and promote recovery after an infection has occurred.
Zinc and vitamin C are required for the maintenance of healthy immune function and the production and activity of specific types of immune cells involved in fighting infection. Taken together, they may help to reduce the frequency, duration and severity of minor respiratory tract infections.