Many people get bronchitis at some point in their life—it is quite common and easily recognised by its cough. Herbs and nutrients have been shown to be effective antibiotic alternatives. Cindy L.A. Jones, PhD, investigates.
Bronchitis refers to an inflammation of the mucous membranes of the bronchi—the main, branching airway passages of the lungs. The inflammation can be caused by infection, smoking, chemical irritation and allergies. It includes symptoms similar to those of a cold: runny nose, tiredness, back and muscle aches, slight fever, and sore throat accompanied by a cough. Like a cold, it typically runs its course in seven to 10 days, but it can also become chronic and last several months.
Those seeking conventional medical help for bronchitis are often treated with bronchodilators and antibiotics. A recent study published in the Journal of the American Medical Association reviewed the prescriptions written in 531 paediatric office visits. The researchers found that antibiotics were prescribed for 46 per cent of patients with upper respiratory tract infections, such as sore throat, for 44 per cent of patients with a common cold, and for 75 per cent of children who presented with bronchitis.1 These levels of antibiotic prescriptions account for a large percentage of the overall antibiotics prescriptions for children, outpaced only by antibiotic prescriptions for otitis media—middle ear inflammation. (Keep in mind that not all bronchitis is caused by bacteria, an obvious reason why antibiotics don't seem to be effective.)
But are antibiotics generally effective in the treatment of bronchitis? Many studies have evaluated the use of antibiotics for the treatment of bronchitis, but with mixed results. Two meta-analyses have combined the results of several small, randomised, controlled and blinded trials to provide a more accurate measurement of overall effectiveness. The first of these, from Syracuse, New York, and Toronto, evaluated nine individual studies totalling 779 patients diagnosed with acute bronchitis.2 Researchers found only a slight advantage to patients taking antibiotics in terms of reduced coughing after one to two weeks. However, other outcomes, including activity limitations and feeling ill, did not improve in the groups receiving antibiotics. The authors also found that 85 per cent of patients showed no improvement with antibiotics.
The second study, at the University of California-San Francisco School of Medicine, examined eight randomised controlled trials regarding the use of antibiotics to treat bronchitis.3 Researchers found a slight advantage in using antibiotics, which gave patients approximately one-half day less of cough and sputum production. The authors suggest, however, that the monetary cost and the side effects associated with antibiotic use outweigh the benefits they provide. Side effects associated with antibiotic use include allergic reactions, diarrhoea, fever, nausea and vomiting, vaginitis, headache, skin rash, abnormal liver and kidney function, and evolution of resistant bacteria, not to mention expense.4
The problems associated with bacterial resistance to antibiotics have caused so much concern over the past few years that every major medical organisation from the US Centers for Disease Control to the World Health Organisation and the American Medical Association have urged physicians to stop overprescribing antibiotics. The US Food and Drug Administration has proposed that antibiotics be labeled to warn users of the emergence of drug-resistant bacterial strains that have been associated with wanton antibiotic use.5
Bronchitis can become more than just an annoyance, it can interfere with one's ability to perform daily activities. Although no stringent clinical trials have been performed to provide unequivocal evidence that herbs can cure bronchitis, there is more than just an historical and anecdotal basis for their use. Many herbs can provide relief by dilating the smooth muscle of the bronchi to increase air flow, decreasing congestion and inflammation that leads to bronchitis, decreasing pain and boosting the immune system to ward off infections.
Immune-stimulating herbs and supplements include echinacea (Echinacea purpurea), vitamin C, zinc, garlic (Allium sativum), licorice (Glycyrrhiza glabra), plantain (Plantago major) and Korean ginseng (Panax ginseng).
Echinacea, most researchers agree, stimulates the immune system and shortens the duration of an upper respiratory-tract infection. In a recent study on E. purpurea, conducted in Marburg, Germany, researchers concluded that there were no statistically significant benefits for its use in treating upper respiratory-tract infections.6 However, the data from the study indicated that echinacea decreased the risk of acquiring a respiratory-tract infection by 12 per cent and decreased its length from 6.5 days to 4.5 days. This was a randomised, blinded trial with 109 patients, half of whom received a 4mL fluid extract of E. purpurea twice/day for eight weeks.
Vitamin C and zinc may help shorten the duration and intensity of an upper respiratory-tract infection. Although there is some controversy between clinical trials, most researchers have found that vitamin C supplementation of greater than 1g/day shortens the duration and the severity of cold symptoms, both in children and adults.7
No trials have definitively determined an appropriate dose for vitamin C, but it seems to be from 2g, or 2,000 mg/day, up to 12,000mg/day. Caveats: The body can process only 500-1,000mg every two to three hours, so taking it all at once is not recommended. Also, too much vitamin C causes diarrhoea. Vitamin C may be especially beneficial to those who exercise a great deal. It appears that this group of individuals contracts more colds, which may be because physical stress uses up more vitamin C.8
Although a zinc deficiency is associated with a suppressed immune system, whether zinc stimulates the immune system for individuals without deficiencies is still controversial. There is evidence that zinc can inhibit the binding of rhinovirus to cells, thus inhibiting the infection process. A recent meta-analysis at Queen's University in Kingston, Ontario, indicates that zinc gluconate is effective in reducing the duration and severity of cold symptoms for adults. However, it is best taken at the first sign of a cold, 12-15mg every two hours.9
A recent study at the Cleveland Clinic in Ohio, however, found that 10mg oral zinc gluconate, five times daily, was not effective in treating cold symptoms in 249 children from grades 1 through 12.10 More studies should be done before a conclusion is made regarding the use of zinc for children. Because zinc can cause nausea, it should not be taken on an empty stomach and not for more than a week at a time.
Garlic can benefit individuals with bronchitis in a number of ways. Garlic has been documented to relax smooth muscle cells that can in turn relax the bronchi and allow more air to pass through them. Garlic also has documented immunostimulant activity in animals. Thirdly, garlic extracts have antimicrobial properties that can kill unwanted bacteria in the lungs.11 It is a traditional treatment for bronchitis, perhaps because its active agents and volatile oils are secreted through the lungs upon ingestion, directing them just where they are needed.
Licorice has traditionally been used to treat bronchitis and respiratory infections. Licorice acts as an expectorant, which helps bring mucus up from the lungs; as an anti-inflammatory agent; and as an antimicrobial agent. Test-tube and animal studies have suggested that licorice can also stimulate the immune system.12,13 Because of its mucilaginous properties, licorice soothes the throat. Use licorice as a candy, tea, tincture, powdered or whole root.
Too much licorice can have steroidal effects, causing water retention and increased blood pressure. Although a safer form of licorice, known as deglycyrrhizinated licorice, is available, this form is not very effective in treating bronchitis. Individuals with a tendency toward high blood pressure should not use licorice.
Plantain has historically been used to treat problems of the respiratory tract, including bronchitis. It can dilate the bronchi, allowing more air to reach the lungs; it can inhibit inflammation; and it has antibacterial properties.14 A recent study at Uppsala University in Sweden indicates that extracts from plantain can inhibit certain prostaglandins that promote an inflammatory response.15 Newer studies also suggest that plantain has immun-omodulatory effects both in the test tube and in mice, possibly due to its polysaccharides.16,17 A rather old study from Bulgaria found that plantain was effective in relieving symptoms of chronic bronchitis with no toxic effects.18
Korean ginseng was found in a recent study from Italy to be more effective than antibiotics alone in treating bronchitis.19 This nonblinded, randomised trial included 75 patients with acute attacks of chronic bronchitis. Although all patients were given antibiotics, half were also treated with 100mg of a standardised ginseng extract, G115, twice daily for an average of nine days. Bronchial secretions were incubated for bacterial growth each day during the trial. Patients taking ginseng in addition to antibiotics showed decreased bronchial bacterial counts faster than patients taking antibiotics alone, becoming significant on day four of treatment. No bacteria were detected in the ginseng-plus-antibiotic group on day six, whereas the antibiotic-only group required an extra day to be considered bacteria-free. The authors suggest these results are due to the immunomodulating effects of ginseng. Previous studies have found immunomodulating effects for ginseng in vitro.19
The herb world provides us with many options for treating bronchitis. And evidence is accumulating for these natural remedies. Although some ingredients are at present more compelling than others, all of the alternatives listed here should be the focus of investigations and could lead to new product developments.
Cindy L.A. Jones, PhD, is a nutrition writer and educator specialising in the evidence-based use of herbs. She is author of The Antibiotic Alternative (Healing Arts Press, 2000) and Herbs for Healthy Skin (Mushroom ebooks, 2002). She teaches at the Nutrition Therapy Institute of Colorado Inc. in Denver. www.sagescript.com
1. Nyquist AC, et al. Antibiotic prescribing for children with colds, upper respiratory tract infections, and bronchitis. JAMA 1998;279:875-7.
2. Smucny JJ, et al. Are antibiotics effective treatment for acute bronchitis?: a meta-analysis. J Fam Prac 1998; 47:453-60.
3. Bent S, et al. Antibiotics in acute bronchitis: a meta-analysis. Am J Med 1999;107:62-7.
4. Gleckman RA, Czachor JS. Antibiotic side effects. Sem Resp Crit Care Med 2000;21:53-60.
5. Labeling requirements for systemic antibacterial drug products intended for human use. HHS News, US Department of Health and Human Services. http://www.fda.gov/bbs/topics/NEWS/NEW00736.html, 9/20/00.
6. Grimm W, Muller HH. A randomized controlled trial of the effect of fluid extract of Echinacea purpurea on the incidence and severity of colds and respiratory infections. Am J Med 1999;106:138-43.
7. Hemila H. Vitamin C supplementation and common cold symptoms: factors affecting the magnitude of the benefit. Med Hypoth 1999;52:171-8.
8. Anon. Vitamin C and colds in people under physical stress. Nutr Res Newslett 1996;15:101-2.
9. Marshall S. Zinc gluconate and the common cold. Review of randomized controlled trials. Can Fam Physician 1998;44:1037-42.
10. Macknin ML, et al. Zinc gluconate lozenges for treating the common cold in children: a randomized controlled trial. JAMA 1998;279:1962-7.
11. Harris JC, et al. Antimicrobial properties of Allium sativum (garlic). Appl Microbiol Biotechnol 2001;57:282-6.
12. Utsunomiya T, et al. Glycyrrhizin, an active component of licorice roots, reduces morbidity and mortality of mice infected with lethal doses of influenza virus. Antimicrob Agents Chemo 1997;41:551-6.
13. Nose M, et al. Activation of macrophages by crude polysaccharide fractions obtained from shoots of Glycyrrhiza glabra and hairy roots of Glycyrrhiza uralensis in vitro. Biol Pharm Bull 1998;21:1110-2.
14. Samuelsen AB. The traditional uses, chemical constituents and biological activities of Plantago major L. A review. J Ethnopharmacol 2000;71:1-21.
15. Ringbom T, et al. Ursolic acid from Plantago major, a selective inhibitor of cyclooxygenase-2 catalyzed prostaglandin biosynthesis. J Nat Prod 1998;61:1212-5.
16. Gomez-Flores R, et al. Immunoenhancing properties of Plantago major leaf extract. Phytother Res 2000;617-22.
17. Hetland G, et al. Protective effect of Plantago major L. Pectin polysaccharide against systemic Streptococcus pneumoniae infection in mice. Scand J Immunol. 2000 Oct;52(4):348-55.
18. Matev M, et al. Clinical trial of a Plantago major preparation in the treatment of chronic bronchitis. Vutreshni Bolesti 1982;21:133-7.
19. Scaglione F, et al. Effects of the standardised ginseng extract G115 in patients with chronic bronchitis: a nonblinded, randomised, comparative pilot study. Clin Drug Invest. 2001;21:41-45.