Infections of the respiratory system commonly present to the outpatient primary care setting. The first decision for the primary care provider is to determine the appropriate setting for treatment, in hospital or outpatient.1 The second decision is to initiate empiric therapy with or without an initial work-up for the microbial cause of the infection. In the outpatient setting, many cases of respiratory infection are amenable to naturopathic treatment as an alternative to the conventional standard of care. Where necessary, the standard of care treatment should be initiated without hesitation, yet in these circumstances naturopathic treatment may make an excellent adjunct to conventional care and may improve outcomes.
The world over, pneumonia is the most important infectious cause of death in children. Liu et al. (2012) analyzed global mortality figures from 2010 and determined that, of the 7.6 million children annually who do not reach their fifth birthday, two-thirds of them die from infectious causes; pneumonia is the leading cause of infection and death among them.2 In America, the combination of pneumonia and influenza remains the eighth leading cause of death, annually. This makes it the most common infection-related cause of mortality.3
Acute respiratory illnesses may be as routine and self-limited as the common cold or as complicated and life threatening as multilobar pneumonia with multiple or drug-resistant organisms. While many cases of acute respiratory infection in adults are mild, no provider or patient can afford to miss a case that is complicated, becomes complicated, or requires hospitalization. Therefore, the clinical evaluation and assessment of acute respiratory illness, with a focus on community-acquired pneumonia, demands some attention.
Classifications of Pneumonia
Pneumonias are typically divided into categories based on the location of their transmission. There is a high correlation between where the infection is contracted and what the infectious agent is likely to be. The current classification of infectious pneumonias include community-acquired (CAP), hospital-acquired (HAP), ventilator-associated (VAP), and health-care-associated (HCAP).4 We will address CAP almost exclusively in this article, as it is the category most commonly encountered in ambulatory primary care. Bacteria are the most common causes of CAP and have traditionally been divided into "typical" and "atypical" groups. While this distinction is still used, distinguishing between the two on clinical grounds is often not possible.1,5 Evidence indicates that physician judgment is moderately good at ruling out a diagnosis of pneumonia, yet there is an ever-increasing opportunity for us to utilize evidence-based clinical decision-making tools and prediction rules to improve upon this.6
CAP is an infection of the lung parenchyma that is not acquired in a hospital, long-term care facility, or other recent exposure to the health care system. Typical CAP is caused by the gram-positive airway bacterium Streptococcus pneumonia or by Group A strep, Haemophilus influenzae, Staphylococcus aureus, Moraxella catarrhalis, aerobic gram-negative bacteria, and anaerobes. Atypical causes of CAP include numerous respiratory viruses, Mycoplasma pneumoniae, Chlamydophila pneumoniae, C. psittaci, and Legionella species.5
Very often, CAP microbial etiologies are not identified (44%-69%); the most frequently isolated etiologic agent is S. pneumoniae (6%-14%). Viral causes of CAP appear to make up 3% to 15% of cases in the outpatient setting, while Mycoplasma and Chlamydophila account for 5% to 17% and 2% to 14% of identified etiologies, respectively.7-9 When treating CAP empirically, it is therefore important to cover the most common atypical organisms, as their individual incidence is similar to that of viral causes and their combined probability exceeds viral likelihood severalfold.10
History and Physical Evaluation of CAP
The interview of a patient with suspected pneumonia should include questions about animal exposures (especially birds), occupation, recent travel (domestic and international), and sexual history.1 This information is important in the decision-making process about the likelihood of involvement of particular microbes and the appropriate laboratory evaluations to be made.
There are no individual clinical findings or combination of findings that can predict the diagnosis of pneumonia with certainty. Cough and sputum production, pleuritic chest pain, tachypnea (rapid breathing), tachycardia (rapid pulse), dyspnea (shortness of breath), fever, chills, and rigor (a single shaking chill) are common signs and symptoms seen in the setting of CAP. While fever may be present in 75% to 80% of positive cases, chills in 40% to 50%, tachypnea (over 24 breaths per minute) in 45% to 70%, and chest pain in 30%, none of these findings are sensitive enough to rule out the disease in their absence. Pneumonia can present with a protean constellation of symptoms; even gastrointestinal involvement is common as diarrhea, nausea, and vomiting may be among the complaints at the initial evaluation.1,11,12
Tachypnea has a positive likelihood ratio of 3.5 (LR+ = 3.5), for the prediction of CAP in adults when the breathing rate is over 24 per minute. Moreover, it is an important sign of pneumonia in the elderly.12 Up to 70% of those over 65 years old with CAP will demonstrate tachypnea. Confusion or functional mental status change and weakness are also important clinical signs of CAP in the older population.13 While the absence of fever and absence of sputum production significantly reduce the likelihood of CAP in adult patients, these indicators are unreliable in the older adult population, which tends toward fewer febrile events, in general, and often presents a subtler picture of CAP.7,14
Rales or crackles are present upon pulmonary auscultation in most patients with CAP; signs of lung consolidation are present in about one-third of patients. Of the potential signs, egophony (LR+ = 2.0-8.6), bronchial breath sounds (LR+ = 3.5), dullness to percussion (LR+ = 2.2-4.3), and decreased breath sounds (LR+ = 2.3-2.5) have the best likelihood ratios for predicting the presence of consolidation. Asymmetric breath sounds, increased fremitus, and pleural rubs are very specific for the presence of consolidation, but are often absent clinically.1,14,15
Pulse oximetry should be performed in all patients suspected for CAP. Often a 3- to 5-minute exercise desaturation challenge can unmask important information that may not be obvious during a resting pulse oximetry measurement. Even in the setting of a normal resting measurement, it is abnormal for patients to lose 5% or more from their oxygen saturation reading during exertion.16 Completing a pulse oximetry oxygen desaturation challenge in the office is a simple and straightforward procedure; we believe that the procedure should be used routinely.
Laboratory Testing and Imaging
Initial laboratory testing in suspected CAP is not specific for diagnosis, but is important in predicting mortality and the appropriate context for care. Based on history, risk factors, and potential exposures, a more intensive work-up for the underlying microbial etiology of CAP may be in order. The most indicative laboratory test for the presence of CAP is a white blood cell count (WBC), which will typically demonstrate leukocytosis which may be markedly elevated at 15,000 to 30,000 cells per cubic millimeter and will typically demonstrate a left shift. A WBC value over 10,400/mm3 has a positive likelihood ratio of 3.4 for presence of CAP. Leukopenia may be present instead and is generally an indicator of poor prognosis.12,14
The blood urea nitrogen level (BUN) should be drawn, as it is useful in determining whether the patient is a candidate for outpatient treatment. The blood platelet count is also a useful measure in predicting severe CAP.7 Hypoglycemia, specifically a blood glucose level less than 70 mg/dL at presentation, is an indicator of increased 30-day mortality.18 More recent investigations have considered the value of serum cortisol testing as an independent predictor of CAP severity, prognosis, and mortality.19
The high success rate of empirical therapy for outpatient treatment of CAP (> 95% in some studies), renders routine laboratory testing for infectious etiology optional in the majority of cases of outpatient appropriate CAP.1,12,20 However, it is important to investigate for and recognize when the underlying infectious agent may be of significance to public health or suggestive of a "critical microbe." There are four tests that should be considered based on the history, risk factors, and clinical findings in any case suspected for CAP: pneumoccocal urinary antigen test, Legionella urinary antigen test, sputum cultures, and blood cultures. A full discussion of testing for microbial etiology in the outpatient setting is available in the Infectious Disease Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults (Mandell et al.) and goes beyond what is discussed here.21
It is recommended that any patient suspected for CAP with a history of any travel over the previous two-week period be tested for Legionella infection by urinary antigen testing. Patients who abuse alcohol, show evidence of pleural effusion on chest radiography, or do not respond to outpatient therapy should also be tested for urinary Legionella antigen.
The urinary pneumococcal antigen should be tested in patients who suffer from alcohol abuse or who have chronic severe liver disease of any etiology. Asplenia and leukopenia are also conditions that should prompt this test. As above, when outpatient treatment fails or when there is radiographic evidence of pleural effusion, the urinary pneumococcal antigen test should be completed.
Sputum and blood cultures should be completed in those with a positive pneumococcal antigen test as well as in those with pleural effusion, alcohol abuse, or evidence of cavitary infiltrates on chest radiography. Sputum cultures are also indicated in those with severe obstructive lung disease, those with a positive urinary Legionella antigen test, and those who fail outpatient treatment. Blood cultures are also indicated in those who are asplenic, leukopenic, have severe chronic liver disease, or have a positive urinary pneumoccocal antigen test.21
Routine PA and lateral chest radiograph (CXR) should be performed in the setting of acute respiratory illness if any one of the following is present: core body temperature greater than 100 ºF, pulse greater than 100 beats/minute, or respiratory rate over 20 breaths/minute. It should also be performed if any two of the following are present: decreased breath sounds, crackles/rales, absence of asthma.12,22
When to Hospitalize
The first step in clinical decision-making and patient management in any case of suspected CAP is to decide upon the need for hospitalization.1 A large number of CAP cases will be amenable to outpatient treatment. Moreover, hospitalization of the CAP patient increases risks of certain complications, especially nosocomial infections, superinfections, and thromboembolic events.1 The estimated cost of a single hospitalization for CAP ranges from $3000 to $13,000.23 However, in CAP cases where it is necessary, timely hospitalization can be life-saving. Several predictions rules have been created and validated over recent years to help clinicians safely determine and document the appropriateness of outpatient management or hospital referral of CAP. The most rigorously validated of these measures is the Pneumonia Severity Index (PSI). Despite much redeeming value, the PSI is cumbersome for use in the primary care setting and is hampered by its inability to always recognize the most severe cases of illness.24 The British Thoracic Society has developed the CURB 65 and CRB 65 prediction rules, which are practical in all settings.
The CURB 65 prediction rule uses the parameters of confusion, uremia (BUN >20 mg/dL), respiratory rate (> 30/min), blood pressure (< 90/60), and age (65 years or more) to predict the likelihood of mortality, and therefore the appropriate care setting, for cases of CAP. Each of the five variables in the CURB 65 score is afforded 1 point. A score of 0 to 1 point confers a 30-day mortality risk of less than 2.1% and determines a safe circumstance for treating the patient in the outpatient setting. A score of 2 points confers a 30-day mortality risk over 9% and demands inpatient treatment; patients with scores of 3 or more points should be treated in intensive care as their mortality ranges from 15% to 40%.7
A validated, clinically useful modification of the CURB 65 score is the CRB 65 score. CRB 65 omits the measurement of serum BUN levels, which may not be immediately available in all clinical settings. The score is based on confusion, respiratory rate, blood pressure, and age, only. As a result, only patients with a CRB 65 score of 0 are deemed appropriate for outpatient management. Several other factors also need to be considered when determining the relative safety of treating CAP in the outpatient setting.25
The evaluation of comorbidities and social circumstances of each patient suspected for CAP is instrumental when deciding upon the appropriateness of outpatient management. The functional status and living situation of the patient must be considered, as must her/his ability to comply with treatment and maintain oral intake. The history of substance use should also be considered. Comorbidities that predispose patients to complications or more severe illness should also be taken under consideration and include COPD, diabetes, immunosuppressive therapies and conditions, liver or kidney disease, asplenism, and alcoholism.26
In those deemed appropriate for outpatient treatment, follow-up should occur in person or by phone within the first 24 to 48 hours after initiating therapy for assessment of response to treatment. In cases which conform to treatment expectations at the 24- to 48-hour mark, in person follow-up should be completed one to two weeks after initiating treatment. Management of progressive, worsening, or recalcitrant cases should occur on a daily basis with persistent consideration toward increasing the level of care.
Monitoring at Follow-Up
Appropriate monitoring at each follow-up visit should be focused on assessment of resolution of the acute condition as well as that appropriate to any comorbidities. At minimum those parameters should include but are not limited to vital signs, pulse oximetry, cardiopulmonary physical examination, WBC count, BUN level, and CURB 65 or another mortality prediction score. Follow-up chest X-rays are considered unnecessary for CAP patients who are responding to treatment. These can be reserved for patients over 40 years old and/or smokers, and to document resolution or absence of underlying pathological processes.26,27
Conventional Standard of Care
In the outpatient setting, in patients who were previously healthy and have used no antibiotics in the past three months, oral treatment with a single macrolide antibiotic (commonly azithromycin) or doxycycline for 10 to 14 days is considered appropriate initial therapy. However, in patients with comorbidities (chronic heart, lung, liver, or kidney disease, diabetes, alcoholism, malignancy, or asplenia), or in patients whom have undergone antibiotic treatment within the previous three months, a respiratory fluoroquinolone or beta-lactam antibiotic should be added to the standard macrolide regimen. Further discussions of antimicrobial therapies for more complicated cases are available elsewhere.21
Pneumonia prevention is achieved through vaccination and smoking cessation. Pneumococcal vaccination is recommended for everyone over 65 years old and in patients of all ages who are smokers, have asthma, or suffer chronic illnesses, comorbidities, or asplenia.28 The current best practice guidelines recommend vaccination against influenza annually for everyone over 6 months of age.29 Influenza vaccination has been shown effective in the prevention of pneumonia, hospitalization, and death in older persons.30
There is substantial debate about the risk:benefit ratio of vaccination, particularly the influenza vaccination. Conventional experts concede that the effectiveness of the influenza vaccination depends upon host factors and the antigenic similarity between the prepared vaccine and circulating viral strains.21 It is well known that the effectiveness of pneumococcal vaccination may diminish with age and that studies regarding its effectiveness, outside the setting of bacteremia, have been conflicting.31-33
A Case in Point
As a cautionary anecdote, in the spring of this last year a 48-year-old male with several important comorbidities, including COPD and diabetes, presented to us for an urgent appointment; he had abstained from influenza and pneumococcal vaccinations the previous season. He presented to our clinic confused, obtunded, and in moderate respiratory distress with clinical signs of pneumonia. We referred him to a local emergency department; he was admitted to the hospital, where he remained for the following seven days. The isolated microbial etiology of his condition was influenza A virus. It is impossible to know whether flu vaccination would have prevented this occurrence, but it was not likely to have made the circumstances any worse.
Natural Medicine for Respiratory Infections
The natural medicine treatment of pneumonia will most often assume an adjunctive role to that of the conventional standard of care. By contrast, in viral upper respiratory infections, bronchitis, most cases of uncomplicated flu and the like, natural treatments will often step to the fore and provide solutions when conventional medicine may have little to offer.
In our practice, treatments for upper respiratory infections fall broadly into one or more of three categories: mucolytic/expectorant, antimicrobial, and supportive. Each patient's treatment plan will incorporate at least one treatment from each of these areas, and often more. We will outline some of the treatments that we use most frequently and refer to the prevailing evidence for each wherever possible.
Mucolytics and Expectorants
We often tell patients that water (oral intake) is the best natural mucolytic. While we can find no randomized controlled trials, meta-analyses, or systematic reviews to support that notion, common sense dictates that it is likely still a factual statement, at least in healthy individuals. The most recent Cochrane reviews of inhalation of heated, humidified air for the common cold and bronchiolitis in young children conclude that there is insufficient evidence to recommend the treatment.34,35 We still routinely recommend steam inhalation to thin phlegm and increase expectoration. We typically recommend the addition of aromatic herbs or essential oils to the steam, and we will address that point further momentarily. Care is required in the use of steam inhalation as scalds and burns (including burns of the respiratory tract), are possible, but used safely the treatment remains a low-cost source of relief for many patients.
We routinely reach for N-acetylcysteine (NAC) as a well-tolerated and effective mucolytic and expectorant. NAC has been utilized in this application for bronchitis and other pulmonary conditions for decades.36-38 In trials, doses of 600 to 1200 mg daily in divided doses have demonstrated significant improvements in respiratory conditions. In one study of chronic bronchitis, patients taking NAC recorded 65% fewer sick leave days taken compared with the placebo group.39 In a study of elderly patients, there were significant reductions in influenzalike episodes and severity of symptoms during those episodes in the group taking NAC versus the placebo group.40,41 We generally recommend a dose of 600 mg, two or three times daily.
Several polyphenols have demonstratedmucolytic and expectorant effects. In vitrostudies have examined their effects on the expression of genes responsible for mucin hypersecretion as well as on cytokine induction of those genes and on the mucocilary elevator and cilary beat frequency in the nasal mucosa. In particular, quercetin, epigallocatechin-3-galate from green tea, and -gingerol from ginger effectively inhibited mucous secretion while maintaining normal ciliary function.42-44
A host of botanical medicines have been traditionally used as expectorants. Unfortunately, there is little or no mention of several of them in the current medical literature, but the experiences of our mentors and ourselves have led us to their routine use. We typically customize a formula of expectorant and antimicrobial botanicals for each patient with respiratory illness. Botanicals that we frequently choose include horehound, grindelia, prickly ash, lobelia, cayenne, ginger, and licorice. Prickly ash is underappreciated, as it seems to be an excellent expectorant and flavoring agent.
The literature on licorice (Glycyrrhiza glabra) demonstrates compelling evidence with regard to its mucolytic and antimicrobial effects. In vitro studies on animal tissue cultures have demonstrated that the constituent prunetin can regulate secretion and production of mucin by acting directly on airway epithelial cells.45 Investigations of the antiviral properties of licorice in humans have focused primarily on hepatitis viruses B and C and HIV, though actions against copious other viruses including influenza, respiratory syncitial virus and the herpesviridae family of viruses have been studied in tissue cultures and animal models. The authors of a 2007 licorice review article conclude, "The data reviewed showed that several constituents of licorice roots have a potential as effective alternatives in combating a wide variety of respiratory, hepatic and systemic viral diseases by general immune modulatory and membrane effects, as well as specific effects on enzyme activity and expression related to selected viruses."46-68 Moreover, in vitro research has demonstrated the antibacterial effects of constituents from licorice on the common respiratory bacteria Streptococcus pyogenes, Haemophilus influenzae, and Moraxella catarrhalis.69
Thyme (Thymus vulgare), especially thyme oil, has shown potent antimicrobial activity in several in vitro studies. Disk diffusion studies have demonstrated strong inhibition of multidrug-resistant strains of Staphylococcus, Escherichia, Pseudomonas, and Enterococcus genera isolated from human oral and abdominal cavities, respiratory and genitourinary tracts, and skin.70,71 Thyme and cinnamon essential oils (EO) have demonstrated antimicrobial activity against S. pyogenes, S. pneumonia, and S. agalactiae as well as Klebsiella pneumonia, Haemophilus influenza, Staphylococcus aureus, and Stenotrophomonas maltophilia in vitro.72
Eucalyptus globulus EO has demonstrated in vitro effects against H. influenza, H. parainfluenzae, and S. maltohilia as well as slightly weaker activity against S. pneumonia and S. agalactiae.73
A multicenter, double-blind, placebo-controlled trial was conducted by Ben-Arye et al. (2010) that examined the effects of a spray containing Eucalyptus citriodora, Eucalyptus globulus, Mentha piperita, Origanum syriacum, and Rosmarinus officinalis EO versus a placebo spray for changes in severity of the most debilitating symptom (sore throat, hoarseness, or cough) of upper respiratory tract infections over a short period. The spray brought about significant and immediate improvements in symptoms.74 We frequently recommend the addition of a few drops of any one of these to a steam inhalation to volatilize it and deliver it directly to the respiratory epithelium.
We will often dispense, through the insertion of cotton tip applicators into the nasal meatus, an essential oil blend called Nasosympatico. The formula blends eucalyptus EO 3.75 mL, thyme EO 3.75 mL, peppermint EO 3.75 mL, and lavender EO 0.8 mL in a base of sweet almond oil 4.5 oz. (135 ml). Used by us most often for chronic sinus infections, the formula and delivery method is a valuable adjunct to upper respiratory tract viral or bacterial infections as elucidated above. The technique itself has been attributed to traditional osteopathic medicine, and other naturopathic physicians have reported effectiveness from its use in chronic sinusitis.75
Echinacea species have been the subject of much research over the past decades. Clinical trial data are conflicting as are the preparations and species of echinacea used in various studies. The existing data make it appear that preparations of the aerial parts of Echinacea purpurea demonstrate the greatest potential for clinical effect.76,77 Data suggest that echinacea demonstrates its antiviral effect against viral membranes and therefore may be more potent in the early stages of infection or during viral shedding and transmission with less effect against intracellular viruses.76-79 The effects of echinacea have also been demonstrated on immune cell function, trafficking, and cytokine expression leading to other potential infection-fighting mechanisms beyond its direct virucidal effects.80-83 Echinacea has demonstrated varying effects against particular upper respiratory pathogens in vitro, with very promising effects demonstrated against group A strep bacterial and H. influenzae, but very little effect against MRSA or K. pneumoniae.84,85
Elderberry (Sambucus nigra) has demonstrated interesting and robust in vitro effects against bacteria and viruses, especially the influenza viruses.86-88 Much of that research has focused on a particular proprietary preparation of elderberry. Three clinical trials of that proprietary elderberry preparation have demonstrated moderate effects against the severity and duration of the symptoms of influenza viruses and upper respiratory tract infections.86,89 The authors of recent reviews on elderberry concede that the data seen to date is promising, but that clinical trials have demonstrated a moderate effect, at best, and that further studies are needed to "demonstrate clinical effects beyond any doubt."90
There have been several studies published on the antimicrobial effects of vitamin D. An excellent review article on the antimicrobial research behind the use of supplemental vitamin D was produced by Youssef et al. (2011), and describes the state of the literature to date. Those authors conclude that vitamin D boosts innate immunity through modulation of cytokines and antimicrobial peptides.91 B and T cell, monocyte, and macrophage activation are all increased by vitamin D.92,93 Moreover, the enhanced clearance of invading organisms exhibited by its use may help to minimize direct invasion of infectious agents at sites such as the respiratory tract.94-98
Goldenseal, Berberis species, mullein, St. John's wort, olive leaf, osha, lomatium, horehound, and bee propolis are agents that we use routinely. Goldenseal (Hydrastis canadensis) shows some in vitro activity against the H1N1 strain of influenza A.99 The effects of Berberis species, and the isoquinoline alkaloid berberine in particular, have demonstrated in vitro effects against respiratory pathogens such as S. aureus, and K. pneumoniae, and C. albicans.100-103 It has also been shown to increase mucous production and may therefore be a soothing expectorant.104 Mullein (Verbascum thapsus) has demonstrated antibacterial activity against S. aureus, K. pneumoniae and has a rich traditional use as a soothing expectorant.105,106 St. John's wort (Hypericum perforatum) has demonstrated excellent antimicrobial activity against MRSA and other gram-positive bacteria.107 Olive leaf (Olea europa), osha (Ligusticum porteri), and lomatium (Lomatium dissectium) all have a rich traditions of use in treatment of upper respiratory infections, especially viral infections, and olive leaf has shown some antiviral activity in vitro.38,108 Horehound (Marrubium vulgare) essential oil has shown antibacterial and antifungal properties.109,110 Bee propolis is another agent that we employ frequently; it has demonstrated repeated antimicrobial and anti-inflammatory properties in vitro.111-121
Supportive Natural Therapies
Supportive therapies take many forms and may be immunomodulatory, hydrating, nutritional, or any of several others. In this instance, we will also use the term to refer to those treatments that are traditional or rationally expected to be physiologically helpful in spite of the fact that evidence surrounding their use may be conflicting or absent.
Two clinical trials have shown the importance of supplemental zinc in the treatment of childhood pneumonia. The first of these demonstrated that 20 mg/day of zinc supplementation in 270 children aged 2 to 23 months hospitalized for pneumonia accelerated the rate of recovery and reduced the number of days spent in hospital.122 The second trial demonstrated no effect of zinc supplementation on the amount of time to normalization of respiratory rate, oxygen saturation, or body temperature in 352 children aged 6 to 59 months with severe pneumonia; however, there was a significant reduction in mortality in the treated group compared with the placebo group.123
The use of vitamin C in the treatment and prophylaxis of pneumonia has been the subject of literature review and authors conclude that the present evidence is insufficient and contradictory, but promising, especially in those with low plasma level of vitamin C.124
Vitamin E has been demonstrated to significantly enhance immune function in the elderly in several investigations.125
In our practice, we routinely recommend postural drainage, contrast hydrotherapy, short wave diathermy, and at-home mustard plasters in the supportive treatment of respiratory infections. The Cochrane Database has reviewed chest physiotherapy treatments for pneumonia in adults and concludes that they may not be warranted as routine adjunctive treatment, but conceded that the review is hampered by limited evidence.126 Unfortunately, none of these other treatments have been reported in recent medical literature; yet anecdotally we find them helpful enough to continue recommending them.
Perhaps our favorite routine supportive treatment recommendation to patients with acute infections is a blend of herbs affectionately referred to as "Chinese chicken soup." It contains lotus seed, Lycium fruit, Dioscorea rhizome, Polygonatum rhizome, black fungus, Codonopsis root, astragalus root, and longan fruit. Patients are instructed to cook the herbs in water with vegetables and chicken or tofu. Other than the astragalus root, all of the herbs are edible after cooking. Several demonstrate nonspecific immunomodualtory properties and one in particular demonstrates antiviral activity.127-131
The best existing evidence base for any natural treatment in respiratory infections appears to be use of the botanical medicine andrographis (Andrographis paniculata). Several excellent reviews of this botanical medicine are available and demonstrate effects on symptom alleviation and prevention of upper respiratory tract infection.132-135 We have not used it extensively in our practice before now, but we certainly intend to consider it as an option in all appropriate cases from here forward. Current evidence appears to indicate that 400 mg, three times daily, demonstrates the best effects in acute illness.133
Scrupulous scrutiny for contraindications and potential interactions is demanded when constructing a natural medicine treatment plan that is adjunct or alternative to the standard of care in the treatment of any condition. Many of the treatments mentioned in this article are contraindicated in pregnancy or have other important potential adverse interactions. Excellent resources are available for the purpose of contraindication screening, including the online databases Natural Standard and Natural Medicines Comprehensive Database and the texts Herb Contraindications and Drug Interactions by Brinker and Herb, Drug, Nutrient Interactions by Stargrove, Treasure, and McKee. It also bears noting that respiratory conditions always have the potential to become critical or life-threatening at a moment's notice, even when previously stable.
Unfortunately, as is so often the case, there is a dearth of evidence regarding the safety and efficacy of many natural treatments that we routinely recommend for respiratory infections. This should ring loud and clear as a general call to increase the amount and the rigor of the research that we do in the disciplines of natural medicine. Every clinician has a part to play and can contribute to the evidence base of natural medicine; even a single case report is one more piece of evidence than currently exists.
Respiratory conditions, infectious and otherwise, are highly amenable to natural medicine treatments in our experience. There are many combinations of therapies that can improve patient outcomes and satisfaction. Appropriate decision-making regarding diagnosis and context of care in respiratory illnesses is our responsibility as physicians; the application of natural therapies in their management is the art and science of natural medicine.
To contact the authors or for further information:
Dr. Martin Milner and
Dr. Jeremy Mikolai
Heart & Lung Wellness Program
Center for Natural Medicine Inc. (CNM)
1330 SE Cesar E. Chavez Blvd.
Portland, Oregon 97214
503-232-1100, ext. 303
These authors have no financial conflicts of interest to declare.
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