The use of beta-agonists and the risk of death and near death from asthma

Asthma mortality in California, 1960-1989. Demographic patterns and occupational associations

We analyzed asthma mortality rates in California during the years 1960 to 1989. Sex- and race-specific rates were stratified by age group (0 to 4, 5 to 34, 35 to 64, and 65+ yr) and for all ages directly standardized to the 1970 U.S. age distribution. Observed and expected asthma deaths were also calculated by occupation for the period 1979 to 1981 among persons aged 16 to 64 yr using data from the California Occupational Mortality Study. Asthma mortality rates were strongly associated with increasing age, but no consistent differences were observed between men and women. Mortality rates among blacks under age 65 yr were two to four times the corresponding rate among whites between 1960 and 1989, but this difference was not observed for those over age 65. Asthma mortality rates were calculated for Hispanics and Asians from 1985 to 1989. In this time period the asthma mortality rate ratios for Hispanics were 0.4 to 0.8 compared with the age-stratified rates among whites, 0.1 to 0.2 times the black rates in age categories under 65, and 0.5 times the rate for blacks ages 65 and above. Asthma mortality rates among Asians under 65 yr of age were similar to rates for whites, but for Asians 65 yr of age and over the rate ratios for males and females compared with whites were 1.8 and 1.1, respectively. A decrease of approximately 50% in asthma mortality occurred from 1960 to 1970, and a marked increase occurred between 1975 and 1989.(ABSTRACT TRUNCATED AT 250 WORDS)

An explanation of the asthma paradox

The morbidity and mortality associated with asthma are rising, despite increased usage of anti-asthma medications. This report attempts to provide a plausible hypothesis for the "asthma paradox." The hypothesis involves the role of mast cell degranulation as an endogenous anti-inflammatory mechanism to prevent antigens from entering the lower airways and to limit the extent of the subsequent repair process. By treating symptoms of asthma with drugs such as beta 2 agonists that inhibit mast cell degranulation, increased inflammation is allowed to occur, which may lead to the chronic appearance of excess repair tissue and the acceleration of the disease process.

Comparison of the effects of salmeterol and formoterol on airway tone and responsiveness over 24 hours in bronchial asthma

The recent development of new beta 2-adrenoceptor agonists with a duration of action in excess of 12 h may change strategies in the treatment of bronchial asthma. This study aims at the direct comparison of the main representatives of this new class of drugs, formoterol (F) and salmeterol (S), in asthmatic patients over the course of 24 h. Twelve patients with mild bronchial asthma participated in a double-blind, randomized, placebo-controlled clinical trial. In a dose-finding study we determined the protective and bronchodilating effects of 12 and 24 micrograms F aerosol vs 50 and 100 micrograms S 30 min after inhalation. In a 24-h study we investigated the effects of 12 micrograms F and 50 micrograms S on airway tone and responsiveness. Bronchial responsiveness was assessed as the dose of methacholine necessary to decrease FEV1 by 20%. In the dose-finding study, compared with placebo, all doses of F and S equally increased FEV1 (p < 0.003) and protected against inhaled methacholine (p < 0.0001). In the 24-h study 12 micrograms F and 50 micrograms S increased FEV1 and significantly protected against methacholine-induced bronchoconstriction up to 24 h (p < 0.05), compared with placebo. Phase and amplitude of the circadian variation of FEV1 and airway responsiveness were not affected. Clinically recommended doses of aerosolized F (12 micrograms) and S (50 micrograms) have a duration of action up to 24 h and are equally effective at bronchodilation and protection in acute experiments in patients with mild bronchial asthma.

The effect of 10, 50 and 200 micrograms inhaled fenoterol on exercise induced asthma

In a randomized, double-blind cross-over study we investigated the protective effect of low doses of fenoterol on the airway response to exercise during cold air breathing. In 12 mild to moderate asthmatics with exercise induced asthma (mean age: 26 [range 19-25] years), mean FEV1 87% of predicted, exercise challenges were performed under control conditions and 30 min after the inhalation from a metered dose inhaler of either placebo, or 10, 50, and 200 micrograms fenoterol within a 4 week period. Airway response was determined by measuring specific airway resistance, sRaw. Standardization of exercise challenges was achieved by individually maintaining a constant respiratory heat exchange, with an average (range) of 1.24 (0.98-1.61) kcal/min. Fenoterol aerosol was an effective bronchodilator at all doses administered (P < 0.05), with 200 micrograms significantly more effective than 10 micrograms. Mean sRaw (s.e.m.) pre vs maximal post exercise after control conditions, placebo and 10, 50, and 200 micrograms fenoterol aerosol was 12.9 (1.4) vs 41.8 (6.3), 13.1 (1.6) vs 41.3 (6.3), 9.6 (1.5) vs 26.6 (6.2), 7.9 (0.9) vs 16.4 (3.6) and 5.5 (0.5) vs 7.4 (0.9) cmH2O.s. The protective effect of fenoterol against exercise induced bronchoconstriction was dose-dependent and was significantly different from placebo at 50 and 200 micrograms (P < 0.05). From these observations we suggest that in mild to moderate asthmatics 50 micrograms of fenoterol in a dose which is sufficient to protect against this naturally occurring stimulus.

Nedocromil sodium

OBJECTIVE

To summarize the available pharmacokinetic and pharmacologic data on nedocromil sodium and to present representative clinical trials of this new agent in both mild-to-moderate and severe chronic asthma and allergic rhinitis. Adverse effects are reviewed.

DATA SOURCES

A MEDLINE search was used to identify pertinent literature, excluding reviews and foreign-language articles. All available English-language studies were reviewed.

DATA EXTRACTION

Pivotal and representative studies are discussed relating to the following issues: pharmacology and pharmacokinetics, management of patients with non-steroid-dependent and steroid-dependent asthma, comparison with sodium cromoglycate (cromolyn), comparison with inhaled beclomethasone dipropionate, management of exercise-induced asthma, use in children with asthma, and use in allergic rhinitis.

DATA SYNTHESIS

Nedocromil sodium is chemically grossly unrelated to cromolyn but has similar pharmacology, pharmacokinetics, and therapeutic benefits. Although ineffective in relieving acute asthma attacks, nedocromil appears to be superior to placebo in lessening the severity of chronic asthma and protecting against allergen-induced asthma when taken as chronic prophylaxis. Single doses attenuate exercise-induced asthma. It is also effective in the management of allergic rhinitis. Results have varied when nedocromil has been compared with cromolyn or inhaled beclomethasone. Studies to date indicate that, overall, nedocromil is not significantly better than cromolyn and is no better than or is inferior to inhaled beclomethasone, although individual response appears to be variable, with no identifiable predictive factors.

CONCLUSIONS

Individual patients may receive marked improvement from nedocromil therapy, but there are no factors that identify which patients will respond. Nedocromil may be particularly useful in adults who frequently fail to respond to cromolyn.

Do bronchodilators adversely affect the prognosis of bronchial hyperresponsiveness?

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Enhancement of airway reactivity to histamine by isoprenaline and related beta-adrenoceptor agonists in the guinea-pig

1. The effect of isoprenaline, adrenaline and salbutamol on airway reactivity to histamine was observed in anaesthetized, ventilated guinea-pigs. Airway reactivity was determined before and 20 min and 90 min after a 30-min i.v. infusion of each agonist by constructing cumulative dose-response curves from breath-by-breath measurements of the effect of different rates of i.v. infusion of histamine on lung resistance (RL) and dynamic compliance (Cdyn). 2. (+/-)-Isoprenaline infused i.v. for 30 min at a rate of 0.4 mumol h-1 kg-1 caused bronchodilatation and a fall in blood pressure. Recovery to starting values of RL and Cdyn occurred within 20 min of stopping the infusion. 3. Reactivity to histamine was greatly enhanced when measured 20 min and 90 min after stopping the infusion of (+/- )-isoprenaline. This was not an effect of the prior infusion of histamine or of the dissolving solution. 4. Infusion of (-)-isoprenaline for 30 min at a rate of 0.2 mumol h-1 kg-1 also enhanced reactivity to histamine. However, enhancement of reactivity to histamine was not demonstrable after infusion of (+)-isoprenaline at equal or higher dose rates. 5. Infusions of bronchodilator concentrations of adrenaline and salbutamol also enhanced airway reactivity to histamine, but the bronchodilator effect of salbutamol lasted longer than that of isoprenaline or adrenaline and the development of hyperreactivity was delayed. 6. After acute bilateral vagotomy, infusion of (+/- )-isoprenaline enhanced airway reactivity but only at the highest dose of histamine. 7. (+/-)-Isoprenaline did not enhance contractile responses to histamine in isolated preparations of first branch bronchi. 8. We conclude that the bronchodilator effect of activating beta-adrenoceptors in the airways of guinea pigs is followed by a more persistent state of hyperreactivity to histamine.

Ketotifen inhibits exacerbation of allergic airway hyperreactivity by racemic salbutamol in the guinea pig

In passively sensitized anesthetized guinea pigs, intravenous infusion of low doses of antigen ovalbumin induced a marked increased responsivity of the airways to intravenous injection of leukotriene C4. Sustained infusion of racemic salbutamol intensified responses to leukotriene C4 both before and after infusion of ovalbumin. Hyperreactivity as a result of infusion of ovalbumin was inhibited by intraduodenal injection of either hydrocortisone or ketotifen at doses that did not diminish responses to leukotriene C4 in animals not exposed to antigen. Ketotifen, but not hydrocortisone, inhibited the enhanced hyperreactivity associated with infusion of racemic salbutamol.

Changes in the treatment of wheezing children in the emergency department

This study prospectively examined the pharmacologic treatment of all wheezing children presenting to a pediatric emergency department from December 1987 to September 1991 (10,091 cases). There were increasing trends in rate of hospitalization, use of oxygen saturation measurements, use of corticosteroids and beta agents at discharge, and use of aerosolized bronchodilators administered in the emergency department. This cohort shows decreasing trends in use of theophylline and the use of subcutaneous bronchodilators administered in the emergency department. Increasing patient severity could not be confirmed in this cohort. The increase in use of corticosteroids in wheezing children is well supported in the literature. The use of theophylline appears to have significantly declined while there is still some controversy over its recommendations in the literature.

Interaction and dose equivalence of salbutamol and salmeterol in patients with asthma

OBJECTIVE

To examine the pharmacological interaction of salmeterol and salbutamol and to derive an estimate of dose equivalence of salmeterol for airway and systemic effects in patients with asthma.

DESIGN

Randomised double blind crossover study.

SUBJECTS

12 patients with mild asthma.

INTERVENTION

Placebo or salmeterol 50, 100, 200 micrograms given on separate days followed two hours later by inhaled salbutamol in cumulative doses up to 3600 micrograms.

MAIN OUTCOME MEASURES

Change in forced expiratory volume in one second (FEV1), heart rate, plasma potassium concentration, QTc interval, tremor amplitude, and creatine kinase myocardial isoenzyme concentration.

RESULTS

Compared with placebo, the mean (95% confidence interval) changes in FEV1 and heart rate after salmeterol 200 micrograms were 0.61 (0.32 to 0.90) l and 7.0 (3.8 to 10.2) beats/min. Adding salbutamol caused a large increase in FEV1 after placebo (0.69 l) with progressively smaller changes after increasing doses of salmeterol (0.19 l after salmeterol 200 micrograms). Heart rate and QTc interval increased and plasma potassium concentration decreased roughly in parallel on the four study days with a suggestion of convergence at higher doses of salbutamol. Geometric mean dose equivalences for salmeterol 50 micrograms and 100 micrograms compared with salbutamol were 4.9 and 7.8 (mean 6.4) for FEV1 and ranged from 7.1 (2.9 to 17.0) to 12.6 (4.4 to 36.4) for heart rate, plasma potassium, and tremor (mean 9.5).

CONCLUSIONS

The effect of adding salbutamol to salmeterol is largely additive. Weight for weight salmeterol may be up to 10 times more potent than salbutamol. Considering its longer duration of action salmeterol 50 micrograms twice daily could be equivalent to salbutamol in doses up to 500 micrograms four to six hourly.

Issues and advances in the pharmacotherapy of asthma

Evidence is accumulating that inflammation of the airways is directly responsible for the increased bronchial hyperresponsiveness (BHR) and lung function obstruction in asthma. Bronchoprovocation with non-specific, direct bronchoconstrictors (methacholine and/or histamine) can be used as an indirect measurement of inflammation. Thus bronchoprovocation is a useful method for evaluating the long-term benefits of various therapies in asthma. The focus of asthma therapy research is now on the development of anti-inflammatory agents. Inhaled corticosteroids are currently the most potent anti-inflammatory agents in the treatment of asthma and so are generally the most effective in reducing BHR with long-term use. Non-corticosteroid anti-inflammatory agents that are currently available are reviewed. Recent studies have suggested that regular use of inhaled bronchodilators may actually be detrimental in asthma. At this time the data is still inconclusive but certainly warrants the attention of practitioners and requires further research, particularly in relation to the long-acting beta 2-agonists, formoterol and salmeterol.

Biochemical characteristics and cellular regulation of phosphodiesterase IV

Considerable interest has been generated in the potential utility of phosphodiesterase (PDE) IV inhibitors as a novel class of anti-asthmatic agents. Because a detailed understanding of the molecular and biochemical characteristics of any molecular target of interest provides a key ingredient for rational drug design, we cloned a cDNA encoding a PDE IV (hPDE IV) from a human monocyte library and expressed, purified and characterized the recombinant gene product. Purified hPDE IV has kinetic characteristics consistent with native PDE IV isolated from tissue sources. In addition, it is inhibited by rolipram (Ki = 60 nM) and other archetypical PDE IV-selective inhibitors. Purified hPDE IV also contains a high affinity binding site for rolipram (Kd = 2 nM), although the precise relationship between this site and the cAMP catalytic site is not clear. In other studies in which the regulation of PDE IV expression was examined in U937 cells, a human monocytic cell line, prolonged treatment with salbutamol was shown to induce an increase in the activity of PDE IV. This up-regulation of PDE IV activity appears to be mediated by cAMP and occurs at the transcriptional or pretranscriptional level. As a consequence of PDE IV up-regulation, the sensitivity of U937 cells to the inhibitory effects of adenylyl cyclase activators on cell function is greatly diminished. If such regulation of PDE IV occurs in inflammatory cells in vivo, it could have implications for the therapeutic use of beta-adrenoceptor agonists. Specifically, induction of PDE IV activity in asthmatics being treated with beta-adrenoceptor agonists could result in a heterologous desensitization of inflammatory cells to endogenous anti-inflammatory agents (e.g., epinephrine, prostaglandin E2).

The clinical use of beta-receptor agonists: for and against

Although beta-receptor agonists are the most potent and fastest acting bronchodilators available at present, some studies have questioned their current use. Thus, the increase in asthma mortality in the U.K., New Zealand and Australia in the 1960s was linked to an increase in the use of inhaled beta-agonists and has been attributed variously to the toxicity of beta-agonists and especially isoprenaline or to the toxicity of propellant gases in aerosols. In addition, use of these products may cause the patient to delay seeking medical help. Due to the uncertainty concerning beta-agonist use in asthmatic patients, the recommended approach to management of the disease is to use the least possible medication consistent with achieving therapeutic control. Within this framework, drug therapy may be started at a low level and be increased gradually, or maximum treatment may be given at the start, with later reduction. In this context, beta-agonists play a major role and a therapeutic strategy with four steps in the management of asthma is presented, utilizing sodium cromoglycate, nedocromil sodium, inhaled corticosteroids, long-acting oral bronchodilators, anticholinergics, and oral corticosteroids for maintenance treatment and short-acting inhaled beta 2-agonists when needed.

(+/-) isoprenaline revisited: adverse effects of sympathomimetics in asthma

It is a matter of concern that regular, excessive use of contemporary sympathomimetics has been associated with morbidity and mortality from asthma. As a consequence, restrictions on sympathomimetic usage have recently been advocated in asthma management guidelines. he association between excessive use of inhaled (+/-)isoprenaline and an epidemic of asthma deaths in the 1960s provides a precedent; hence, we have reviewed the numerous clinical and experimental reports concerning (+/-) isoprenaline to provide insight into the present controversy.

Anomalous bronchospasm following inhalation of (+) isoprenaline by asthmatics

Sympathomimetics (beta-adrenergic agonists) presently used in asthma therapy comprise racemic mixtures of bronchodilator and non-bronchodilator enantiomers. In a randomized, double-blind placebo-controlled study, asthmatic subjects inhaled a nebulized solution of the non-bronchodilator (+) enantiomer of isoprenaline. Substantial decreased forced expiratory volume (FEV1) was detected in 2 patients and of the remaining 8, a single subject had increased reactivity to histamine 7 h after inhalation of (+) isoprenaline. These effects of (+) isoprenaline may contribute to anomalous effects of (+/-) isoprenaline in asthma.

The beta-2-agonist perplexity: pro and contra sympathomimetic drugs in childhood asthma

The present overview covers recent research results concerning treatment with beta-2-adrenoreceptor agonists in adults and children with asthma. Special care was taken to summarize only papers and abstracts which were published in peer reviewed international journals and to omit chemical company supported brochures and public relations material. There are only a few reports available dealing with the beta-2-agonist dilemma in the pediatric literature and the efficacy and safety of the new long acting beta-2-agonist therapy in childhood asthma is only starting to be investigated. By weighing the current knowledge it is attempted to draw some conclusions for the therapy today.

Cystic fibrosis

Cystic fibrosis, an autosomal recessive disorder, is the most common genetic disease of Caucasians. One in 25 Caucasians are carriers of the gene. The gene is found far less commonly in other races. There are over 230 different alleles of the gene, located on the 7th chromosome. The gene encodes for a membrane protein that functions as an ion channel. The survival of cystic fibrosis patients has been gradually increasing, with a mean survival in 1990 of 28 years. If the current trend of improved survival continues, it is estimated that half of cystic fibrosis patients will be over 18 years old by 1996. Disease is found in many organs including the lungs, sinuses, pancreas, gastrointestinal tract, hepatobiliary system, sweat glands and reproductive tract. The majority of patients die of pulmonary disease. The airways become chronically colonized with bacteria that cannot be eradicated, leading to bronchitis, bronchiectasis, and finally, pulmonary fibrosis with respiratory failure. The pulmonary disease may be complicated by massive hemoptysis and pneumothorax. Patient survival rates have increased because of antibiotic therapy and improved nutrition with pancreatic enzyme replacements. New treatments for the pulmonary disease are under clinical trial and include antiproteases, amiloride, a sodium channel blocker, and DNase. The insertion of the normal cystic fibrosis allele into an animal model using a modified adenovirus with effective transcription suggests that gene therapy may be possible in the future, but safety and technical problems have to be addressed.

Asthma

There is an active inflammatory process in the airways of patients with asthma, even when the patients are asymptomatic. Some of the types of cells involved in this process possess the necessary biologic activities to produce many of the pathophysiologic features of asthma, but the underlying mechanisms have not yet been elucidated. Reducing the severity of the inflammatory process appears to be a reasonable goal of therapy, with potential long-range implications for the morbidity of asthma. Whether this theoretical benefit will be realized awaits further observation.

Asthma in the 1990s. A new approach to therapy

Asthma has been shown to be an inflammatory disease. Therefore, it makes sense to base treatment strategies on the selection of an appropriate anti-inflammatory agent, with bronchodilators being used as effective rescue medications. Because of recent concerns raised in the literature about the safety of long-term use of beta 2 agonists, early and appropriate medication in the form of inhaled corticosteroids or cromolyn sodium is recommended for daily control of asthma symptoms, long-term patient management, and prevention of acute exacerbations.

Patient education

Only recently has it been appreciated that the considerable morbidity of asthma can be reduced with tools readily available to every physician who treats children. The pharmacotherapeutic armamentarium has been strengthened by better understanding of the pathogenesis of asthma, the impact of inflammation, and the role of preventive therapy. The task remains to put this expanded knowledge to use to help a larger number of children with asthma and their families to diminish the impact that the disease has on their lives. Concomitant with increased understanding of the pathophysiology of asthma and the medications used to control the process has been a greater appreciation of the role of co-management or self-management. Several programs have been developed to help parents and children with asthma gain better control over the disease, thus decreasing morbidity and significantly improving quality of life. These programs are available to physicians and health care organizations, and it is strongly recommended that asthma education, both as a formal course and in the physician's office, be regularly incorporated into the care plan for every child with asthma.

Management of chronic asthma

The treatment of asthma is changing to reflect the importance of inflammation in the disease pathogenesis. Medicines that alter the inflammatory response are the cornerstone of therapy for patients with persistent symptoms. Bronchodilators are important in acute care, but in chronic illness they are adjuvant therapy. Patient education is essential for successful outcome.

Crisis in asthma care

Reports of increases in both hospitalizations and deaths due to asthma have provided a sense of crisis in asthma care. This article examines issues concerning this sense of crisis. The authors review current trends in prevalence, morbidity, hospitalization, and mortality from asthma and examine possible reasons for changes that have occurred. A review of data suggesting that asthma can result in irreversible, chronic airway obstruction is presented. Finally, the authors discuss the role of the primary care physician in the management of asthma.

Management of acute asthma

Patients with acute asthma experience increased airway obstruction, increased work of breathing, and ventilation-perfusion mismatch. Careful observation and assessment of the patient are fundamental for successful treatment. Therapy is dictated by the severity of the acute episode. Prevention of subsequent flares of asthma needs to be initiated as the patient convalesces.

Relation of measures of asthma severity and response to treatment to outcome in acute severe asthma

BACKGROUND

It would be helpful if patients with asthma who require admission to hospital for an acute attack could be identified.

METHODS

The relation between the severity of an attack of asthma as determined by admission assessment and the eventual outcome was studied in 52 asthmatic patients aged 14 to 44 years and admitted to an asthma emergency room. The patient's history, including medication and previous admissions to hospital, was recorded and a clinical assessment, including a full inspiratory and expiratory flow-volume loop, was performed on four occasions: on admission, at two hours and at 12-18 hours after the start of a standardised treatment, and two weeks later on an outpatient basis. Patients who were discharged and who had an uneventful follow up at the two week assessment were defined as good responders. Patients who had to be admitted to hospital after 12 to 18 hours or were readmitted during the two weeks, or both, were defined as poor responders.

RESULTS

Thirty eight patients were good responders and 14 were poor responders (seven admitted at 12 to 18 hours, seven returned to hospital). All four patients with a raised arterial carbon dioxide tension (PaCO2) (> or = 6 kPa) and the three with cyanosis were in the poor responder group, and this group had lower peak expiratory flow (PEF) values (21% v 30% predicted) on admission. There was, however, considerable overlap in PEF between the two groups and no clinical measure was able to distinguish between the good and the poor responders reliably. Poor responders had a history of more chronic systemic steroid administration, regular use of inhaled beta agonists, and asthma related hospital admissions. Nearly all the subjects showing a good response to standardised treatment had a PEF > 75% predicted and an FEV1 > 65% predicted 12 to 18 hours after the start of treatment.

CONCLUSION

Prediction of outcome at admission was not possible in individual patients. A history of poor long term control of asthma, a PEF < 30% of predicted, a PaCO2 > or = 6 kPa, the presence of cyanosis, and lack of early response to treatment indicated a group of asthmatic patients who are less likely to respond to conventional emergency treatment over a short period.

Tolerance to the nonbronchodilator effects of inhaled beta 2-agonists in asthma

BACKGROUND

Tolerance to the direct bronchodilator effects of beta 2-agonists does not appear to occur in asthma. However, it is not known whether this is true for the nonbronchodilator effects of these agents, which protect the airways against bronchoconstrictive stimuli.

METHODS

We investigated whether tolerance develops to the protective effect of inhaled terbutaline on airway responsiveness to the bronchoconstrictors methacholine (which acts directly on airway smooth muscle) and AMP (which acts indirectly by stimulating the release of mediators from mast cells) during sustained treatment with terbutaline. In a randomized, double-blind, crossover study, 12 patients with mild asthma each inhaled a single dose of terbutaline (500 micrograms) or placebo before a challenge with a series of doubling doses of inhaled methacholine or AMP, before and after treatment for seven days with 500 micrograms of terbutaline four times daily or placebo.

RESULTS

Before the seven days of treatment with terbutaline, a single dose of terbutaline reduced airway responsiveness to methacholine by 2.7 doubling doses (95 percent confidence interval, 1.9 to 3.5), but it had an even greater protective effect against AMP, reducing airway responsiveness by 3.8 doubling doses (95 percent confidence interval, 2.7 to 4.9; P less than 0.001). After seven days of treatment with terbutaline, the protective effect of terbutaline against methacholine decreased to 2.2 doubling doses (95 percent confidence interval, 1.3 to 3.0; P = 0.04), and that against AMP decreased even more, to 1.7 doubling doses (95 percent confidence interval, 1.1 to 2.4; P less than 0.001). By contrast, the bronchodilator response to terbutaline was unchanged during seven days of treatment with this agent.

CONCLUSIONS

We observed tolerance to the nonbronchodilator actions of the inhaled beta 2-agonist terbutaline in patients with mild asthma, an effect that may be more pronounced in mast cells than in bronchial smooth muscle. This property of beta-agonists may constitute a drawback to their regular use in patients with asthma.

The Pharmacological Treatment of Ambulatory Chronic Obstructive Pulmonary Disease Patients

Because of the widespread prevalence of chronic obstructive pulmonary disease (COPD) and the important role of drug therapy in its management, there is significant opportunity for the pharmacist to interact with COPD patients. Whether educating patients or other health care providers about COPD, a knowledge of the treatment options and their correct application in these patients is essential for pharmacists today. This article reviews the pharmacological management of ambulatory COPD patients, including the roles of β-agonists, anticholinergics, theophylline, steroids, oxygen, and other treatment modalities. Copyright © 1992 by W.B. Saunders Company