Prevention and Management of Lung Infections - Naturopathic Approaches

Respiratory Infections — An Introduction

One of the most common yet stubborn illnesses many of us are plagued with are respiratory infections, most commonly acute bronchitis, and pneumonia. Not only are they disruptive and painful to deal with at the time of the infection, but it is also typical for someone to experience lingering effects of the infection for weeks after. It is reported that the cough associated with such infections can last up to four weeks after the initial infection.^[1] Symptoms common to all infections are fever and fatigue.

Acute bronchitis is caused by inflammation of the bronchiole tree — the tubes that bring air in to inflate the lungs. When infected, the bronchial airways become narrowed and clogged with mucous, making it difficult for air to pass in to the lungs. Inflammation also causes these airways to spasm, producing a nagging, persistent cough that can be dry or wet. Characteristic symptoms of bronchitis include wet, spasmodic cough that can be productive or nonproductive; wheezing; and trouble taking in full breaths.^[1] Acute bronchitis is most commonly caused by a virus and is rarely caused by bacteria.^[2]

Pneumonia is a term that describes a breathing condition typically caused by an infection of the lungs. There are a number of causes of pneumonia, viral pneumonia, such as the flu virus, being the most common cause of infection. Pneumonia can also be caused by bacteria, most commonly Streptococcus pneumoniae, which typically follows a viral infection — this type of infection is called a secondary bacterial infection. Symptoms of pneumonia can be similar to bronchitis, perhaps more severe, and can create a productive cough producing yellow, green, or blood-tinged mucous.^[3]

Currently, typical treatment prescribed for respiratory infections are antibiotics. However, repeated doses of antibiotics have been found to be associated with recurrent infection and weakened immunity, as well as illness associated with other types of microbes, such as yeast infections and Clostridium difficile.^{[4, 5]} Due to the viral nature of acute bronchitis, the use of antibiotics as a form of treatment is questionable, posing the question whether the positive effects of this preventative measure outweigh the negative effects of antibiotics on the immune system.^[2] It is imperative that we seek interventions that will strengthen the immune system, resulting in reduced severity, duration, and incidence of respiratory infections, as well as providing prevention of future infections. Despite the improvement people report using natural remedies to decrease the severity and duration of their respiratory illnesses, there is very little evidence in the scientific community confirming these positive outcomes.

 Probiotics and Immune Health

The intestinal walls are the main barrier and interaction between the immune system and the external environment. The intestines house a large portion of our immune system called the galt-associated lymphoid tissues (GALT), a system that highly determines the strength of our immune system. Probiotics influence the immune system by providing a protective barrier of “good” bacteria to compete with the overgrowth of “bad” bacteria.^[6] Reasons good bacteria could be out of balance can be associated with lifestyle factors such as poor diet. However, recurrent antibiotic use is one of the most common reasons for our probiotic flora to be in a state of imbalance or “dysbiosis”. Many conditions linked to immune imbalance, such as allergies, eczema, asthma, and rheumatoid arthritis, to name a few, have been found to be associated with dysbiosis.^[7] Probiotics have been extensively researched for their positive effects on improving the immune system, especially in these conditions, by promoting immunoregulation — balancing the proinflammatory and anti-inflammatory systems.^{[7, 8]} The balancing effects of probiotics on the immune system have been demonstrated in acute respiratory infections. Studies have found daily probiotic supplementation is a safe way to reduce cough and duration of antibiotic treatment in children, and has also been found to reduce severity, length, and the number of respiratory tract infections in healthy adults over the winter season.^{[9, 10, 11]} Current evidence has found that probiotics are not associated with widespread negative side effects, or can produce very mild gastrointestinal symptoms such as gas.^[12] Dosage for probiotics may vary. Standard dosing for probiotics naturopathic doctors are comfortable with range from 5 to 200 billion colonies, daily.

Botanicals

There are a number of popular herbs used to treat infections associated with acute bronchitis and pneumonia. Some of the most popular herbs found in commercial herbal preparations today include Echinacea spp., goldenseal, and elderberry, all used for their antiviral and antimicrobial properties. By reducing viral and bacterial load, these herbs can reduce duration and severity of symptoms associated with infections, but do not directly have an effect on the cough. There are a number of herbs that have been traditionally used to relieve cough; this article will describe just a few.

Coltsfoot

Coltsfoot (Tussilago farfara) is a perennial herb that is part of the Asteraceae family. The flowers have long been used in China for their favourable effects on the respiratory system. It has been found to exhibit antispasmodic, antimicrobial, anti-inflammatory and soothing properties, making it useful for treating irritating coughs associated with bronchitis, asthma, and pneumonia.^[13] It has also been traditionally used to treat the respiratory infection tuberculosis.^[14] This traditional use of coltsfoot has sparked preliminary studies to examine the biochemical properties that may explain these positive effects on pulmonary conditions. An in vitro study performed by Zhao et al. found a large number constituents found in coltsfoot exhibited antitubercular properties,^[14] while another has found the extremely rich flavonoid content in coltsfoot can explain its anti-inflammatory properties in general.^[15] The leaves have been found to contain rich levels of zinc, which could also contribute the anti-inflammatory and immune-boosting abilities.^{[13, 15]} However, coltsfoot contains constituents called pyrrolizidine alkaloids, which are known to have damaging effects on the liver and can promote cancer.^[13] It is recommended not to use coltsfoot for longer periods of time, and it is strongly recommended to consult with a medical practitioner familiar with this herb before using.

Thyme

Thyme (Thymus vulgaris) is a culinary herb part of the lamiaceae family, whose leaves and flowers have been traditionally used to treat spasmodic coughs. Traditionally, infusions of thyme sweetened with honey would be given to those with bronchitis, whooping cough, sore throats, and congestion.^[16] The reason for its excellent effect on coughs can be attributed to its antispasmodic and expectorant properties.^[13] A double-blind, placebo-controlled trial found that a syrup containing thyme herb and ivy leaves significantly reduced coughing fits by 50% by day 2 of treatment in adults with acute bronchitis with at least 10 coughing fits a day.^[17] The main active constituent of thyme is the volatile oil thymol, which has been praised for its antispasmodic effects on the trachea, as well as its antimicrobial properties against a number of bacteria, including Salmonella hyphimurium, Staphylococcus spp., and seven strains of Gram-positive and Gram-negative bacteria.^[16] The antimicrobial and antispasmodic properties could justify thyme as an extremely useful herb in bacterial pneumonia. Thyme has been found have no contraindications or herb-drug interactions.^{[13, 16]} Side effects from thyme are rare, but it has been linked to allergic dermatitis through skin-patch testing, and to occupational asthma by inhalation challenges.^[16]

Mullein

Mullein (Verbascum thapsus) is a biennial plant that grows native in Europe, and Asia. It is part of the scrophulariaceae family and its vast properties to treat and heal the respiratory tract paved its way in to North America as a medicinal herb, most commonly for irritating coughs with bronchial congestion.^[18] The leaves and flowers have been traditionally used for respiratory conditions, due to their toning effects on the mucous membranes of the lower respiratory tract. The demulcent qualities which soothe the irritated respiratory tract are attributed to its rich polysacchride content, while the saponin constituents stimulate fluid production, which can help with expectoration of tough mucus.^[13] Mullein has also been found to have anticatarrhal properties, which make it an excellent herb to use when a productive cough lingers after the infection.^[16] The anti-inflammatory effects are exerted through the iridoid glycosides, allowing the mucous membranes to heal. Mullein has also been found to decrease pain in the chest and can relax a spasmodic cough.^{[13, 18]} These properties make mullein most useful in treating bronchitis associated with dry, hard, spasmodic coughs with soreness.^[13] Mullein has also been shown to exhibit antiviral characteristics in in vitro studies, suggesting it may be a useful herb in viral-induced respiratory conditions.^{[19, 20]} No side effects or drug interactions have been reported for this herb, and it is generally considered safe used as indicated.^[13]

Discussion

Acute infections of the respiratory tract are extremely common in our society. Typically caused by a viral infection, which is a self-limiting condition, these infections can progress to a secondary bacterial condition, or can result in prolonged symptoms, such as persistent cough. Though typical treatments for these conditions involve antibiotic treatment, this can produce ineffective results, such as in viral infection, or can render the immune system weak, making one susceptible to further or more severe infections. It is important that we use treatments that not only make our immune systems resilient against infections, but can reduce the severity and duration of these infections, such as through preventative probiotic supplementation. There are a number of herbs used traditionally that work through antiviral and antibacterial actions in order to fight infection, but also have properties useful to easing coughs and soothing the respiratory tract, such as coltsfoot, mullein, and thyme. There is a need for more studies to confirm these effects; however, traditional use of these herbs, along with their low toxicity and side effects, make them wonderful complementary options to help ease symptoms associated acute respiratory infections.