Agent Name	Discussion
Aids to smoking cessation	Smoking cessation is the most significant intervention that has the potential to slow the progression of chronic obstructive pulmonary disease Chitkara and Sarinas (2002). Pharmacological therapy for tobacco dependence is added to counseling to increase the likelihood of success. Nicotine replacement therapy is most commonly given as a transdermal patch, with nicotine gum, nasal spray, inhaler, or lozenge used to counteract breakthrough cravings. Smoking cessation is more likely to succeed when nicotine replacement therapy is used in combination with the antidepressant bupropion. With this combination, nicotine is gradually withdrawn while bupropion is maintained for 12 months or longer.
Beta-2 adrenoceptor agonists	Those with acute bronchitis frequently exhibit wheezing and other signs of reversible bronchoconstriction. Although chronic obstructive pulmonary disease is characterized by bronchoconstriction that is incompletely reversible following administration of a bronchodilator, long-term therapy with bronchodilators decreases the symptoms of airflow limitation in individuals with chronic bronchitis. Thus, bronchodilator therapy is central to the management of chronic bronchitis and its acute exacerbations Chitkara and Sarinas (2002). Inhalation is the preferred route of administration because it maximizes the delivery of the agent to the lungs and minimizes systemic side effects. Short-acting beta-2 adrenoceptor agonists such as albuterol produce rapid bronchodilation by action on the beta-2 adrenoceptors on the airway smooth muscle. Anticholinergics are the preferred drugs for the treatment of acute bronchitis Smuncy et al (2003). In the treatment of chronic bronchitis, beta-2 adrenoceptor agonists may be used on a scheduled basis or as-needed to treat acute bronchospasm. Beta-2 adrenoceptor agonists are also used in the treatment of acute exacerbations of chronic bronchitis McCrory et al (2001). The efficacy of long-acting beta-2 adrenoceptor agonists such as salmeterol is under study. The bronchodilatory effect of anticholinergics is additive with that of beta-2 adrenoceptor agonists. Combination products that deliver a metered dose of a beta-2 adrenoceptor agonist and ipratropium can simplify drug administration.
Anticholinergics	Those with acute bronchitis frequently exhibit wheezing and other signs of reversible bronchoconstriction. Although chronic obstructive pulmonary disease is characterized by bronchoconstriction that is incompletely reversible following administration of a bronchodilator, long-term therapy with bronchodilators decreases the symptoms of airflow limitation in individuals with chronic bronchitis. Thus, bronchodilator therapy is central to the management of chronic bronchitis and its acute exacerbations Chitkara and Sarinas (2002). Inhalation is the preferred route of administration because it maximizes delivery of the agent to the lungs and minimizes systemic side effects. Anticholinergic bronchodilators such as ipratropium block the muscarinic receptor-mediated bronchoconstriction, mucus secretion, and bronchial vasodilation that result from vagal stimulation of the airways. The duration of action of ipratropium is longer than that of the short-acting beta-2 adrenoceptor agonist bronchodilators. It can decrease the volume of sputum produced without altering its viscosity. An ipratropium inhaler may be used in acute bronchitis where bronchospasm is problematic Smuncy et al (2003). In chronic bronchitis, ipratropium is a mainstay of therapy Chitkara and Sarinas (2002). Some individuals who are non-responsive to beta-2 adrenoceptor agonists derive symptomatic relief with ipratropium. The bronchodilatory effect of ipratropium is additive with that of beta-2 adrenoceptor agonists. Combination products that deliver a metered dose of a beta-2 adrenoceptor agonist and ipratropium can simplify drug administration.
Theophylline	Although chronic obstructive pulmonary disease is characterized by bronchoconstriction that is incompletely reversible following administration of a bronchodilator, long-term therapy with bronchodilators decreases the symptoms of airflow limitation in individuals with chronic bronchitis. Thus, bronchodilator therapy is central to the management of chronic bronchitis and its acute exacerbations Chitkara and Sarinas (2002). Theophylline exerts a wide variety of physiological actions including central nervous system stimulation, cardiac stimulation, and smooth muscle relaxation. Its major action on the lung results from the inhibition of the cyclic nucleotide phosphodiesterases that break down cyclic AMP and cGMP, second messengers that mediate bronchodilation. Theophylline also inhibits the release of inflammatory mediators by immune cells. Its narrow therapeutic index, potentially life-threatening side effects, and numerous drug interactions have made theophylline a second-line therapy for chronic bronchitis. While its efficacy as compared to other bronchodilators is questionable, a subset of patients appears to benefit from theophylline. Lower therapeutic doses used in combination with a beta-2 adrenoceptor agonist may be beneficial in some cases.
Oxygen	Oxygen therapy is indicated when the symptoms of chronic obstructive pulmonary disease (COPD) become severe enough to limit activities of daily living Chitkara and Sarinas (2002). It may also be used as-needed during exercise in those who don't qualify for continuous oxygen use. Oxygen therapy reduces mortality and improves quality of life in persons with severe COP D. It is also useful in the management of acute exacerbations of chronic bronchitis McCrory et al (2001).
Antibiotics	Although antibiotics are frequently prescribed for acute bronchitis, most cases are viral in origin, rendering them useless. Antibiotic therapy does not decrease the duration of illness, limitation of activities, or loss of work time in most cases of acute bronchitis Fahey et al (1998), Smuncy et al (1998), Bent et al (1999). Thus, the frequency of antibiotic use can safely be reduced without affecting patient outcomes Gonzales et al (2001). In the rare cases in which acute bronchitis is caused by Mycoplasma pneumoniae or Chlamydia pneumoniae, fluoroquinolones, tetracycline, and macrolides are effective Gonzales and Sande (2000). Acute bronchitis caused by Bordetella pertussis may be treated with erythromycin, but it is only effective early in the course of illness. The role of bacterial infection in acute exacerbation of chronic bronchitis remains controversial. In those exacerbations in which purulent sputum is a predominant feature, the extent of bacterial eradication correlates with the degree of resolution of inflammation associated with the exacerbation White et al (2003). The United States National Heart, Lung, and Blood Institute and the World Health Organization recommended that antibiotics be given for acute exacerbations in which there is evidence of infection, e.g. increased sputum production, change in sputum color, and/or fever Pauwels et al (2001). Commonly used antibiotics include amoxicillin-clavulanate, azithromycin, and several cephalosporins and fluoroquinolones.
Glucocorticoids	Although glucocorticoids are frequently employed in the therapy of chronic bronchitis, their use is controversial Chitkara and Sarinas (2002). Glucocorticoids block immune cell activation, cytokine release, and mucus secretion in vitro, yet only 10-20% of individuals with chronic obstructive pulmonary disease actually respond to them. It is impossible to predict who will respond to glucocorticoids. Indeed, those who benefit from oral glucocorticoids during acute exacerbations may not realize any value from chronic inhaled glucocorticoid use. Systemic glucocorticoids (e.g., prednisolone) are used for the treatment of acute exacerbations of chronic bronchitis and can alleviate symptoms, decrease hospitalization time, and reduce relapse rate among steroid-responsive individuals McCrory et al (2001). Chronic treatment with inhaled glucocorticoids such as fluticasone produces a modest reduction in the incidence of acute exacerbations, with no impact on the rate of functional decline. The United States National Heart, Lung, and Blood Institute and the World Health Organization recommend long-term maintenance therapy with inhaled glucocorticoids in symptomatic patients who exhibit a documented spirometric response to glucocorticoids or who have an FEV-1 of <50% of predicted and suffer from repeated exacerbations requiring antibiotic or glucocorticoid therapy Pauwels et al (2001). Systemic glucocorticoids should be used in the management of acute exacerbation, but chronic treatment should be avoided due to the potential for severe adverse effects.
Vaccines	Because influenza vaccines significantly decrease morbidity and mortality in persons with chronic bronchitis, annual influenza vaccination is recommended Pauwels et al (2001). The pneumococcal vaccine has been used in patients with chronic bronchitis, but there are insufficient data to support its general use for this purpose.
Non-steroidal antiinflammatory drugs	Non-steroidal antiinflammatory agents such as ibuprofen and antipyretic pain relievers, such as acetaminophen, may be used to lessen the symptoms of the acute phase of acute bronchitis (e.g., fever, muscle aches) Gonzales and Sande (2000).
Antiviral drugs	In cases of acute bronchitis caused by influenza A, amantadine or rimantadine may be effective if given within 48 hours of the onset of symptoms Gonzales and Sande (2000). These drugs block the proton channel required for the dissolution of the viral ribonucleoprotein complex early in the process of replication. Zanamivir and oseltamivir are effective against influenza A and B and, like amantadine and rimantadine, must be taken within the first 48 hours of illness. These drugs inhibit neuraminidase, a viral surface glycoprotein involved in the release of progeny virus and in the spread of infection from cell to cell.