Interaction of inhaled beta 2 agonist and inhaled corticosteroid on airway responsiveness to allergen and methacholine. Regular versus symptomatic aerosol bronchodilator treatment of asthma. A 3-month comparison of formoterol with terbutaline via turbuhaler. A placebo-controlled study. Regular use of inhaled albuterol and the allergen-induced late asthmatic response. Rebound increase in bronchial responsiveness after treatment with inhaled terbutaline. Effects of treatment with formoterol on bronchoprotection against methacholine. Intermittent and continuous salbutamol rotacaps inhalation in asthmatic patients. Changes in bronchial reactivity in asthmatic children after treatment with beclomethasone alone or in association with salbutamol. The effect of inhaled albuterol in moderate to severe asthma. Quality of life in asthma clinical trials: comparison of salmeterol and salbutamol. A comparison of salmeterol with albuterol in the treatment of mild-to-moderate asthma. Salmeterol powder compared with albuterol aerosol as maintenance therapy for asthma in adolescent and adult patients. Effect of regular inhaled albuterol on allergen-induced late responses and sputum eosinophils in asthmatic subjects. Tolerance to the nonbronchodilator effects of inhaled beta 2-agonists in asthma. Effect of regular terbutaline and budesonide on bronchial reactivity to allergen challenge. A placebo-controlled clinical trial of regular monotherapy with short-acting and long-acting beta(2)-agonists in allergic asthmatic patients. Rebound airway obstruction and responsiveness after cessation of terbutaline: effects of budesonide. Effect of regular terbutaline on the airway response to inhaled budesonide. Effects of terbutaline and budesonide on sputum cells and bronchial hyperresponsiveness in asthma. Inhaled formoterol dry powder in the treatment of patients with reversible obstructive airway disease. A 3-month, placebo-controlled comparison of the efficacy and safety of formoterol and salbutamol, followed by a 12-month trial with formoterol. Asthma control during long-term treatment with regular inhaled salbutamol and salmeterol. Short-term regular beta 2-adrenergic agonists treatment is safe in mild asthmatics taking low doses of inhaled steroids. Regular inhaled salbutamol and airway responsiveness to allergen. Tachyphylaxis to systemic but not to airway responses during prolonged therapy with high dose inhaled salbutamol in asthmatics. The effect of regular inhaled albuterol on exercise-induced bronchoconstriction. Comparative efficacy and safety of albuterol sulfate Spiros inhaler and albuterol metered-dose inhaler in asthma. Randomised trial of an inhaled beta2 agonist, inhaled corticosteroid and their combination in the treatment of asthma. Inhaled salbutamol for wheezy infants: a randomised controlled trial. A randomized, 12-week, double-blind, placebo-controlled study comparing formoterol dry powder inhaler with albuterol metered-dose inhaler. Beta2-agonist tolerance and exercise-induced bronchospasm. Asthma control during and after cessation of regular beta 2-agonist treatment. Low-dose formoterol Turbuhaler (Oxis) b.i.d., a 3-month placebo-controlled comparison with terbutaline (q.i.d.). Regular vs as-needed inhaled salbutamol in asthma control. A placebo-controlled, crossover comparison of salmeterol and salbutamol in patients with asthma. Long-term regularly inhaled salbutamol. A comparison of regular with intermittent bronchodilators in asthma patients on inhaled steroids. Comparison of regularly scheduled with as-needed use of albuterol in mild asthma. Asthma Clinical Research Network. Regular albuterol, nedocromil sodium, and bronchial inflammation in asthma.
Regular treatment with salbutamol increases airway responsiveness to allergen but not to methacholine and produces tolerance to the bronchoprotective effect of salbutamol. The current study addresses the effect of inhaled corticosteroid on these aspects of regular beta 2 agonist use. A group of 13 atopic asthmatic subjects free from all asthma medications and remote from allergen exposure were studied. We used a double-blind, random-order, crossover study to compare four 1-wk treatment periods with > or = 1 wk washout: placebo, salbutamol, 200 micrograms four times per day, budesonide, 400 micrograms four times per day, and the combination of salbutamol and budesonide. We measured the methacholine PC20 and the methacholine dose shift produced acutely by 200 micrograms salbutamol after 7 d and the allergen PC15 after 8 d treatment. Blinded medications were withheld for 8 to 10 h before measurements. The methacholine PC20 was not affected by regular salbutamol but increased significantly (p < 0.014) after both budesonide-containing regimens. Neither the dose shift nor its significant reduction by regularly used beta 2 agonist were influenced by the inhaled corticosteroid. The four allergen PC15 values were significantly different from each other. Compared with placebo, the allergen PC15 was 0.6 doubling doses lower after salbutamol (p = 0.021) and 1.3 doubling doses higher after budesonide (p < 0.001); the allergen PC15 was reduced by 0.53 doubling doses from this new baseline (p = 0.039) when salbutamol and budesonide were used together.(ABSTRACT TRUNCATED AT 250 WORDS) Regular treatment with salbutamol or placebo aerosols was compared in a double-blind study in 18 asthma patients. Although symptom scores and respiratory function tests were not significantly different, wheezing attacks requiring additional puffs of a standard salbutamol aerosol were significantly more frequent during the period on placebo when patients were receiving symptomatic treatment only. Thus regular treatment with bronchodilator aerosols provides better control of asthma than symptomatic use alone. Oxis Turbuhaler is a new dry powder formulation of long-acting beta2-agonist formoterol. This study compared the efficacy and safety of regular use of the long-acting beta2-agonist formoterol and the short-acting terbutaline for 3 months in patients with asthma.
                After 1-week run-in, 343 patients received either formoterol 12 microg bid (F) (delivered dose of 9 microg), terbutaline 500 microg qid (T) or placebo qid, in a parallel-group, double-blind, randomized manner. They had a mean of 61% of predicted forced expiratory volume in 1 second (FEV1) and a mean reversibility of 26%. Eighty-nine percent used inhaled corticosteroids.
                During run-in mean morning peak expiratory flow (PEF L/min) for F was 366 and 348 for T, and 344 for placebo (P). The F group improved morning PEF significantly compared with P (P = .0022) and T (P = .0001). Changes from run-in were + 18, -1.5, and +5 L/min after F, T, and P, respectively. The F group was statistically significantly better than P and T in increasing evening PEF and in reducing night-time asthma. The F and T statistically significantly reduced the use of rescue medication compared with P. The bronchodilating response to the study drug and to an additional 1.25 mg terbutaline was of the same magnitude before and throughout the study. No statistically significant treatment-by-time interaction was observed (P > .20). There were no adverse effects of clinical relevance.
                Formoterol Turbuhaler, 12 microg bid, was more effective than terbutaline Turbuhaler, 0.5 mg qid, and placebo. Regular use of formoterol or terbutaline did not significantly influence the response to additional inhalation of terbutaline. We have recently demonstrated that a 2-week course of inhaled albuterol 200 micrograms four times daily caused a near doubling of the allergen-induced early asthmatic response. We hypothesized that this might extend to the more clinically relevant late asthmatic response.
                We studied 11 patients with atopic asthma who were free from all medications including inhaled beta 2-agonists for more than 4 weeks. We performed a double-blind, random-order, crossover study, comparing the effect of 1-week treatment periods of albuterol 200 micrograms four times daily and placebo 2 puffs four times daily on the early and late asthmatic responses to the same dose of allergen.
                Regular use of albuterol did not influence the baseline forced expiratory volume in 1 second (FEV1) (3.40 vs 3.42 L, p = 0.84) or the baseline methacholine provocative concentration causing a 20% fall in FEV1 (PC20) (geometric mean, 2.4 mg/ml vs 1.9 mg/ml, p = 0.38). However, all aspects of the allergen-induced asthmatic response were increased. After the 1-week albuterol treatment, the early asthmatic response was slightly greater (21.1% vs 17.9% FEV1 fall, p = 0.26), the late response was greater (23.1% vs 13.2% FEV1 fall, p = 0.0027), and the allergen-induced increase in airway responsiveness (change in log methacholine PC20) was greater (0.37 vs 0.20, p = 0.045).
                One week of albuterol treatment (200 micrograms four times daily) increased the late asthmatic response and allergen-induced increase in airway responsiveness. This suggests that the combination of regular use of inhaled beta 2-agonist and allergen exposure may cause more airway inflammation than allergen exposure alone. To investigate whether cessation of regular beta-agonist treatment results in an increase in bronchial responsiveness, two double-blind, randomised crossover studies were done. Subjects with mild asthma were investigated to determine the course of change in bronchial responsiveness, measured as the provocative dose (PD20) of histamine that caused a 20% fall in forced expiratory volume in 1 s after short-term and longer term treatment with an inhaled beta-agonist. In the first study in 8 subjects, 500 and 2000 micrograms terbutaline thrice in 1 day protected against histamine-induced bronchoconstriction, and the increase in PD20 compared with placebo remained high throughout the day and overnight. In the second study 8 subjects received placebo or terbutaline 750 micrograms thrice daily for 14 days. The protection afforded by terbutaline against histamine-induced bronchoconstriction on day 14 was less than that on day 1 by 40% in the morning and 82% in the afternoon. On day 15 PD20 was lower after stopping terbutaline than placebo, with a maximum difference of 1.5 (95% CI 0.6-2.5) doubling-doses of histamine 23 h after the end of treatment. Thus treatment with terbutaline for 1 day did not result in any rebound increase in bronchial responsiveness. Treatment for 2 weeks impaired the ability of terbutaline to protect against histamine-induced bronchoconstriction, and was followed by a rebound increase in bronchial responsiveness after cessation of treatment. In addition to their bronchodilatory effects, beta(2)-agonists protect against bronchoconstriction, such as that caused by methacholine challenge. However, tachyphylaxis to this beneficial effect develops after chronic use of beta(2)-agonists. We studied whether the frequency or dose of treatment with a long-acting beta(2)-agonist (formoterol) affects the degree of bronchoprotection afforded against methacholine challenge and to compare this with the effects of a short-acting beta(2)-agonist (terbutaline).
                In a randomized, parallel group, double-blind study at two centers, patients with stable asthma of mild to moderate severity who were treated with inhaled corticosteroids were treated with formoterol 6 micrograms twice daily, 24 micrograms twice daily, 12 micrograms once daily; terbutaline 500 micrograms four times daily; or placebo. Treatments were given by dry powder inhaler for a period of 2 weeks. Of the 72 patients who were enrolled, 67 completed the study. Methacholine challenge was performed to calculate the provocative dose that caused a 20% fall in forced expiratory volume in 1 second at baseline (unprotected) after an initial 1-week run-in without beta(2)-agonists, 1 hour after the first dose of study treatment, and again 1 hour after 7 and 14 days of study treatment.
                Each of the four active treatments exhibited significant tachyphylaxis (P < 0.05) to protection against methacholine challenge when comparing first/last dose (as geometric mean protection ratio versus baseline): formoterol 24 micrograms twice daily (9.6-fold/1.6-fold), 12 micrograms once daily (7.1-fold/2.2-fold), 6 micrograms twice daily (6.2-fold/2.3-fold), and terbutaline 500 micrograms four times daily (2.9-fold/2.0-fold). There were no significant differences among treatments after 2 weeks in bronchoprotection against methacholine challenge. For all formoterol regimens, the bronchodilator response 1 hour after inhalation was maintained over the 2-week treatment period. Diurnal control of morning and evening peak flow was significantly better with formoterol 24 micrograms twice daily than with terbutaline.
                Tachyphylaxis to bronchoprotection against methacholine challenge develops after 2 weeks of therapy with formoterol, a long-acting beta(2)-agonist, at all three dosage regimens that were tested. In contrast, the bronchodilator effects of formoterol were maintained during the 2 weeks of treatment. We studied 18 asthmatic patients over an 8-week period. Each patient received for 4 weeks continuous and for 4 weeks intermittent salbutamol rotacaps (400 micrograms) using a double-crossover technique. No significant differences were found between the two treatment regimens as judged by daily card scores and daily PEFR (both a.m and p.m.). Lung Function tests performed monthly in the hospital showed no significant differences between two treatments or the development of bronchial beta-adrenoreceptor resistance. Airway inflammation is consistently present in patients with severe asthma. The combination of inhaled steroids and bronchodilators may be useful both for treating symptoms and improving the underlying inflammatory condition. We have compared the effect of beclomethasone dipropionate (BDP) combined with salbutamol (S), BDP alone, and placebo, on the severity of bronchial responsiveness in 30 children with allergic asthma during the period of specific allergen exposure. In children treated with BDP alone, PC20-FEV1 methacholine was 0.66 +/- 0.54 at the beginning and 1.91 +/- 2.11 at the end of the study period (p greater than 0.05). In children treated with BDP + S PC20, methacholine was 1.21 +/- 1.43 at the beginning and 4.22 +/- 3.88 at the end of the study (p less than 0.05). The group of children treated with placebo had a PC20-FEV1 methacholine of 0.79 +/- 0.61 at the beginning of the study and 0.80 +/- 0.46 at the end of the study. The results of the present study show that maintenance treatment with inhaled beclomethasone combined with salbutamol may lead to greater improvement in bronchial hyperreactivity than treatment with inhaled beclomethasone dipropionate alone. Some recent clinical investigations suggest that regular use of inhaled bronchodilators may lead to deterioration in asthma control.
                The purpose of this study was to evaluate the effect of albuterol dosing schedule on clinical outcome in subjects with moderate to severe stable asthma.
                Seventeen adults were randomized to two 15-week treatment periods in a double-blind crossover design. Throughout the study, subjects were instructed to take two inhalations four times daily from an unlabeled "test" canister. In the four times daily and as-needed (QID + PRN) period, this canister contained albuterol; in the as-needed (PRN) period, it contained placebo. A "rescue" albuterol canister was available for as-needed use at all times. Inhaler actuations from both the test and rescue canisters were electronically recorded. Outcome measures included prednisone requirements, morning and evening symptoms and peak expiratory flow rates, total and nighttime rescue albuterol use, and asthma-specific quality of life.
                The two treatment periods did not differ in symptoms, nighttime albuterol use, or asthma quality of life. During the QID+PRN period both morning and evening peak expiratory flow rates were significantly higher (p < 0.01 and 0.001, respectively) and total rescue use of albuterol was significantly less (p < 0.05) than the PRN period. Days on prednisone tended to be lower in the regular dosing period (p = 0.08).
                In our sample of patients with moderate to severe asthma, four times daily dosing of albuterol did not lead to deterioration of asthma control. Most clinical trials in asthma have focused on outcomes that are primarily of importance to the clinician. Very few have assessed whether patients feel better and can function better in day-to-day activities. The aim of this study was to compare the effects of salmeterol (50 micrograms twice daily), salbutamol (200 micrograms four times a day), and placebo on asthma-specific quality of life and to relate the findings to conventional clinical asthma outcomes. The study was a 12-wk multicenter, double blind, randomized, placebo-controlled crossover trial with each trial medication taken for 4 wk. The subjects were 140 adults with mild to moderate asthma enrolled from 14 respiratory clinics across Canada. Outcome measures were: (1) the Asthma Quality of Life Questionnaire and spirometry at the end of each treatment period; and (2) daily asthma symptoms, morning and evening peak expiratory flow rates (PEFRs), and rescue salbutamol use during the last 14 d of each treatment period. Asthma-specific quality of life, both overall and for the individual domains (activity limitation, symptoms, emotional function, and exposure to environmental stimuli) was better with salmeterol than with placebo (p < 0.0001), and better with salmeterol than with salbutamol (p < 0.001). In both comparisons, differences were not only statistically significant, but most were also clinically important. There were moderate correlations between change in quality of life and change in clinical outcomes.(ABSTRACT TRUNCATED AT 250 WORDS) An effective, long-acting bronchodilator could benefit patients with asthma who have symptoms not controlled by antiinflammatory drugs. We compared a new long-acting, inhaled beta 2-adrenoceptor agonist, salmeterol, with a short-acting beta 2-agonist, albuterol, in the treatment of mild-to-moderate asthma.
                We randomly assigned 234 patients (150 male and 84 female patients 12 to 73 years old) to one of three treatment groups: one group received 42 micrograms of salmeterol twice daily, one received 180 micrograms of albuterol four times daily, and one received placebo. Treatment was assigned in a double-blind fashion, and all patients could use supplemental inhaled albuterol as needed during the 12-week treatment period.
                Measurements of the forced expiratory volume in one second, performed hourly for 12 consecutive hours, showed that a single dose of salmeterol produced a greater mean area under the curve than two doses of albuterol taken 6 hours apart (6.3 vs. 4.9 liter.hr, P < 0.05). The difference was significant on day 1 and at week 4 of the study, but not at week 8 or 12. Salmeterol was also more effective than albuterol or placebo (with albuterol taken as needed) in increasing the morning peak expiratory flow rate: salmeterol induced a mean increase of 24 liters per minute over the pretreatment values, as compared with a decrease of 6 liters per minute with albuterol (P < 0.001) and an increase of 1 liter per minute with placebo (P = 0.002). The mean overall symptom score was improved most by salmeterol treatment (P < 0.05), with the number of days with symptoms and of nights with awakenings decreasing by 22 percent and 52 percent, respectively; there were no differences in results between albuterol treatment and placebo administration. We found no evidence of tolerance to the bronchodilating effects of salmeterol, and adverse reactions to all the treatments were infrequent and mild.
                For the management of mild-to-moderate asthma, salmeterol given twice daily is superior to albuterol given either four times daily or as needed. Two multicenter, randomized, double-masked, placebo-controlled studies involving 451 adolescent and adult patients with mild-to-moderate asthma compared the efficacy and safety of salmeterol powder 50 micrograms twice daily with albuterol 180 micrograms four times daily or placebo (with albuterol as needed) for 12 weeks. Patients had forced expiratory volume in 1 second (FEV1) of 50% to 80%. Throughout the 12-week treatment period, the mean change from baseline in percentage of predicted FEV1 was significantly greater with salmeterol than with placebo; mean area under the curve for FEV1 was significantly greater with salmeterol than with albuterol or placebo. Significant improvements in morning and evening peak expiratory flow, percentage of nights without awakening, and asthma symptoms were observed with salmeterol. Salmeterol was well tolerated, and no clinically significant changes in electrocardiographic activity were observed. Treatment with inhaled beta(2)-agonists immediately before allergen inhalation inhibits allergen-induced early, but not late asthmatic responses (LAR). By contrast, 2 wk treatment with inhaled albuterol increases airway responses to inhaled allergen. We examined the effects of regular albuterol treatment on allergen-induced increases in inflammatory cells in blood and induced sputum. Ten mild, stable allergic asthmatics inhaled albuterol (800 micrograms/day) or placebo for 7 d in a controlled, randomized, double-blind, crossover study. Allergen inhalation was performed 12 h after the final dose. Methacholine airway responsiveness and blood samples were analyzed before and 24 h after, and induced sputum was obtained before, 7 h and 24 h after allergen. Allergen significantly reduced methacholine PC20, increased blood eosinophil numbers, and numbers of sputum neutrophils, EG2 positive and metachromatic cells (p < 0.05), without significant differences between treatments. Albuterol treatment significantly increased the LAR compared to placebo treatment (p = 0.003) and significantly enhanced the number of sputum eosinophils (p = 0.009) and sputum ECP (p = 0.04) at 7 h but not 24 h post-allergen (p > 0.05). We conclude that regular use of inhaled albuterol significantly increases the LAR to inhaled allergen, in association with an increase in the number of sputum eosinophils and the release of ECP, suggesting albuterol increases the late response by increasing eosinophil influx into the airways. 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.
                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.
                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.
                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. There is a transient rebound increase in bronchial reactivity to histamine and methacholine following regular treatment with an inhaled beta 2-agonist. We set out to determine whether the response to allergen was increased after cessation of regular inhaled terbutaline and whether concomitant inhaled budesonide modifies this response. In a double-blind, double-dummy, parallel group design we studied 41 subjects (37 evaluable) with mild asthma who were allergic to Dermatophagoides pteronyssinus, grass pollen, or cat fur. Following a 2 wk run-in period, subjects underwent a fixed three-dose allergen challenge based on their previously determined provocative concentration of allergen producing a 20% fall in FEV1 (PC20) before starting terbutaline 1,000 micrograms or placebo three times daily and budesonide 800 micrograms or placebo twice daily for a period of 2 to 4 wk (mean 18 d). The same three-dose allergen challenge was repeated 33 h after stopping treatment. During treatment evening peak flow values were highest in the terbutaline plus budesonide group. Following regular terbutaline there was no rebound increase in bronchial reactivity to allergen. Following budesonide there was a significantly smaller response to allergen and an increased FEV1 compared with the other three groups, including the budesonide plus terbutaline group. The changes in median (95% CI) allergen PC20 after budesonide, terbutaline, budesonide plus terbutaline, and placebo were 0.79 (0.3, 2.3), 0.11 (-0.4, 0.6), 0.24 (-0.4, 0.5) and -0.47 (-1.5, 0.1) doubling doses (p < 0.01). The respective changes in mean FEV1 were 0.34, -0.16, -0.01, and 0.06 L (p < 0.005). Thus bronchial reactivity to allergen was not increased after regular inhaled terbutaline.(ABSTRACT TRUNCATED AT 250 WORDS) Some recent studies suggest that regular beta(2)-agonist use may result in inadequate control of asthma. It has been hypothesized that this occurs particularly in allergic asthmatic patients exposed to relevant allergens. Moreover, it is still unclear whether this occurs during the use of both short-acting and long-acting beta(2)-agonists.
                Asthmatic patients (n = 145) allergic to house dust mite (HDM) were randomly allocated to monotherapy with a short-acting beta(2)-agonist (SA; n = 48), a long-acting beta(2)-agonist (LA; n = 50), or placebo (n = 47), double blind, double dummy. The study covered three periods: (1) a 4-week run-in period, in which no changes took place; followed by (2) cessation of treatment with asthma medication including inhaled corticosteroids, introduction of allergen avoidance measures (active/placebo treatment) to lower HDM exposure in the active group, and an 8-week washout period to adjust patients to these changes; followed by (3) a 12-week study medication period. At the start of the 12-week medication period, and every 4 weeks thereafter, spirometric measurements (FEV(1) and provocative concentration of histamine causing a 20% fall in FEV(1) [PC(20)]) were performed. Peak flow and asthma symptoms were recorded daily. Additionally, at the start and every 6 weeks thereafter, dust samples were collected from mattresses and living room and bedroom floors to assess HDM (der p 1) concentrations. Effects on FEV(1), PC(20), peak flow, and asthma symptoms were analyzed with repeated-measurement analysis and corrected for the exposure to HDM allergens.
                There were no significant differences among the three medication groups after 12 weeks for FEV(1). However, a significant decrease in mean FEV(1) percent predicted (95% confidence interval [CI]) was observed within the SA group: - 6.6 (- 10.4 to - 2.8) (p = 0.0002). A decrease in geometric mean PC(20) (95% CI) of - 1.2 (- 1.96 to - 0.44) doubling concentration was observed within the SA group (p = 0.05). No significant changes in FEV(1) and PC(20) were observed > 12 weeks within the LA group or the placebo group. There were neither changes in peak flow and asthma symptom scores among the three medication groups nor within the groups. Moreover, none of the parameters showed interactive effects with allergen exposure.
                There were no significant differences among the three medication groups for FEV(1) and PC(20). The within-treatment group comparison showed a significant small decline in FEV(1) for the SA group (but not for the LA group), which could indicate that monotherapy with SAs might have negative effects on FEV(1). This was not seen during regular use of LAS: No clear pathophysiologic mechanism can explain these findings at the moment. Relatively high or low exposure to allergens did not alter these findings. Regular monotherapy with inhaled beta 2-agonists may lead to a temporary increase of airway obstruction and increase of airway responsiveness after cessation of treatment. We investigated whether anti-inflammatory therapy may affect these rebound phenomena. In a double-blind, placebo-controlled study, we assessed lung function (FEV1) and airway responsiveness (PC20 methacholine [PC20]) during and after cessation of 2 wk of regular treatment with placebo and low-dose (250 micrograms) and high-dose (1,000 micrograms) inhaled terbutaline three times daily. Patients with mild allergic asthma (means [+/- SD] age of 28.2 +/- 6.6 yr, mean FEV1% of 91.9 +/- 14.6%, and geometric mean PC20 of 0.25 mg/ml) were studied. One group (n = 16) was randomized to budesonide treatment, 400 micrograms three times daily; the other group (n = 14) to placebo. PC20 and FEV1 were measured 10, 14, 34, and 82 h after the last terbutaline or placebo inhalation. A different method of statistical analysis was used, in that measurements performed at 10, 14, and 34 h were expressed relative to 82 h values in each period as an area-under-the-curve (AUC) value. FEV1 did not significantly change during placebo and budesonide treatment. Mean PC20 and morning and evening peak expiratory flow were significantly higher during budesonide treatment (p < 0.01). PC20 did not significantly change after cessation of terbutaline treatment in both placebo and budesonide treatment groups. AUC-FEV1 values after cessation of treatment with both doses of terbutaline were significantly different from the 82 h values (p < 0.05). The decrease in FEV1 was significantly greater after the last terbutaline and placebo inhalation in the placebo group compared with the budesonide treatment group (p = 0.02). We conclude that cessation of regular treatment after 2 wk with both low-dose and high-dose inhaled terbutaline does not result in a significant rebound airway responsiveness in patients with mild asthma. However, the results suggest a small rebound bronchoconstriction that does not occur when asthmatic patients are also treated with budesonide. The rebound increase in bronchial reactivity and fall in forced expiratory volume in one second (FEV1) following treatment with beta agonists seen in several studies has occurred regardless of concurrent steroid therapy. Little is known about the effect of adding beta agonists to corticosteroids, but in a recent study regular treatment with terbutaline appeared to reduce some of the beneficial effects of budesonide. The effects of budesonide alone and in combination with regular terbutaline treatment on lung function, symptom scores, and bronchial reactivity were therefore examined.
                Sixteen subjects with mild stable asthma inhaled budesonide 800 micrograms twice daily for two periods of 14 days with terbutaline 1000 micrograms three times daily or placebo in a double blind crossover fashion. FEV1 and the dose of histamine or adenosine monophosphate (AMP) causing a 20% fall in FEV1 (PD20) were measured before and 12 hours after the final dose of treatment, and changes from baseline were compared. Seven day mean values for daily morning and evening peak expiratory flow (PEF) values, symptom scores, and rescue medication were compared before and during treatment.
                Morning and evening PEF rose more with budesonide plus terbutaline than with budesonide alone, with a mean difference of 19 l/min occurring in the evening (95% confidence interval (CI) 2 to 36). There was no difference in symptom scores during treatment. Following treatment the mean increase in FEV1 was 150 ml higher with budesonide alone (95% CI-10 to 300). There was no difference between treatments in change in histamine and AMP PD20.
                Evening PEF was greater when budesonide was combined with regular terbutaline. There was no evidence of a difference in bronchial reactivity following the two treatment regimens. The findings of a previous study were not confirmed as the reduction in FEV1 after budesonide and terbutaline was smaller and not statistically significant. Further work is needed to determine whether this disparity in findings in the two studies is due to a type 2 statistical error in this study or a spurious finding in the previous study. Previous studies have shown that the regular administration of short acting beta-agonists can be associated with adverse effects on airway caliber and bronchial hyperresponsiveness (BHR) and that this may occur through a proinflammatory mechanism. The aim was to explore possible adverse effects of high-dose beta-agonist therapy and to assess any adverse interaction with corticosteroids. We undertook a randomized, crossover study to investigate the effects of 6 wk of treatment with regular terbutaline (1 mg four times a day), regular budesonide (400 microg twice a day), combined treatment, and placebo in subjects with mild to moderate asthma. Major endpoints were PD(15) saline, PD(20) methacholine, and induced sputum differential cell counts. Thirty-four subjects were randomized and 28 completed the study. PD(15) saline decreased on terbutaline alone compared with placebo treatment and on combined treatment compared with budesonide alone (mean fold decrease of 0.57 [95% CI = 0.36, 0.90] and 0.65 [95% CI = 0.43, 0.97], respectively). PD(20) methacholine was not affected by the use of terbutaline either alone or in combination with budesonide. The percentage of eosinophils in induced sputum increased during terbutaline treatment alone compared with placebo (median 8.3% versus 4.4%, p = 0.049). The addition of terbutaline to budesonide did not affect the percentage of eosinophils compared with budesonide treatment alone. These findings support the hypothesis that short-acting beta-agonists have a permissive effect on airway inflammation and that when used in high dose there may be an unfavorable interaction with inhaled corticosteroids. Inhaled formoterol is a potent selective beta 2-agonist with rapid onset and at least 12-h duration of bronchodilation. The aim of the study was to compare the bronchodilating effect of inhaled formoterol dry powder (dp) 12 micrograms b.i.d. with salbutamol dp 400 micrograms q.i.d. and placebo in patients with reversible obstructive airway disease (ROAD). The study design consisted of a closed 12-week double-blind, placebo-controlled, multicenter trial followed by an open noncomparative, multicenter, 12-month follow-up trial, in which the tolerability of formoterol dp was assessed. A total of 304 patients (146 men, 158 women) aged 18-79 years, ill during 0.1-64 years, were randomized. No demographic or baseline differences were found among the different treatment groups. The bronchodilating effect of formoterol, assessed by morning premedication PEFR, was significantly superior to placebo (P < 0.0001) and salbutamol (P < 0.0001). Efficacy was maintained during the open follow-up study with 12 micrograms b.i.d. in most of the patients. A few patients, however, needed 24 micrograms b.i.d. to control their ROAD. Formoterol 12 micrograms b.i.d. significantly reduced morning and evening asthma symptoms and sleep disturbances, and reduced significantly the need for rescue medication. The tolerability of the three treatment groups was comparable. In conclusion, formoterol 12 micrograms dp b.i.d. was significantly superior to both salbutamol 400 micrograms dp q.i.d. and placebo, and reduced asthma symptoms significantly. Overall, formoterol showed a tolerability profile comparable to that of salbutamol, and no tachyphylaxis was observed during 1 year of treatment. The adverse effects of long term treatment of asthma with the short acting beta agonist fenoterol have been established in both epidemiological and clinical studies. A study was undertaken to investigate the efficacy and safety of long term treatment with salbutamol and salmeterol in patients with mild to moderate bronchial asthma.
                In a two centre double dummy crossover study 165 patients were randomly assigned to receive salbutamol 400 micrograms q.i.d., salmeterol 50 micrograms b.i.d., or placebo via a Diskhaler. All patients used salbutamol as required for symptom relief. The study comprised a four week run in and three treatment periods of 24 weeks, each of which was followed by a four week washout. Asthma control was assessed by measuring mean morning and evening peak expiratory flow rate (PEFR), a composite daily asthma score, and minor and major exacerbation rates. Washout assessments included methacholine challenge and bronchodilator dose response tests. Analysis was by intention to treat.
                Data from 157 patients were analysed. Relative to placebo, the mean morning PEFR increased by 30 l/min (95% CI 26 to 35) for salmeterol but did not change for salbutamol. Evening PEFR increased by 25 l/min (95% CI 21 to 30) and 21 l/min (95% CI 17 to 26), respectively (p < 0.001). Salmeterol improved the asthma score compared to placebo (p < 0.001), but there was no overall difference with salbutamol. Only daytime symptoms were improved with salbutamol. The minor exacerbation rates were 0.29, 0.88, and 0.97 exacerbations/patient/year for salmeterol, salbutamol and placebo, respectively (p < 0.0001 for salmeterol). The corresponding major exacerbation rates were 0.22, 0.51 and 0.40, respectively (p < 0.03 for salmeterol). For salbutamol the asthma score deteriorated over time (p < 0.01), and the time spent in major exacerbation was significantly longer compared with placebo (12.3 days (95% CI 4.2 to 20.4) versus 8.4 days (95% CI 5.2 to 11.6), p = 0.02). There was no evidence of rebound deterioration in asthma control, lung function, or bronchial hyper-responsiveness following cessation of either active treatment, and no evidence of tolerance to salbutamol or salmeterol.
                Regular treatment with salmeterol is effective in controlling asthma symptoms and reduces minor more than major exacerbation rates. Salbutamol was associated with improved daytime symptoms but subtle deterioration in asthma control occurred over time. Salbutamol should therefore be used only as required. Regular treatment with beta 2-adrenergic agonists is controversial in bronchial asthma. To investigate whether beta 2-adrenergic agonists can be used safely if associated with low doses of inhaled steroids, for a short period, without a deterioration of asthma control, we have examined 24 mild asthmatics. In a parallel, double-blind, placebo-controlled study, 1 week of run-in and run-out period framed 3 weeks of treatment. All patients received inhaled beclomethasone dipropionate (BDP 250 micrograms t.i.d.); after 1 week, 12 patients inhaled 400 micrograms of broxaterol and 12 patients received placebo t.i.d. FVC, FEV1, PD20-FEV1 methacholine, morning and evening PEF, and PEF amplitude % mean were measured before, during, and after treatment. No significant changes were noted in patients receiving inhaled broxaterol. There were no differences in symptoms and the use of rescue medication (salbutamol spray). We conclude that short-term regular treatment with beta 2-adrenergic agonists is not associated with a deterioration in asthma control in mild asthmatics inhaling low doses of steroids. Regular inhaled beta 2 agonist causes tolerance to the acute protective effect of beta 2 agonist against bronchoconstriction induced by chemical stimuli such as AMP, histamine, and methacholine. We examined a more clinically relevant stimulus, inhaled allergen, in a double-blind, cross-over, random-order trial in 13 mild atopic asthmatics, who had not used beta 2 agonist for at least 4 weeks. We compared regular inhaled salbutamol (200 micrograms four times daily for 2 weeks) with placebo (2 weeks) for effects on bronchodilator response, baseline methacholine, and allergen airway responsiveness, and on the acute protective effect of salbutamol against both stimuli. Baseline forced expiratory volume in 1 s (FEV1), bronchodilator response, and methacholine responsiveness were the same during both treatment periods. After regular salbutamol, the allergen PC20 (provocation concentration producing a 20% FEV1 decrease) fell by 0.91 (SD 0.66) (p = 0.0009) doubling doses, and the protective effects of salbutamol on methacholine and allergen were both significantly reduced (p = 0.026 and 0.025, respectively). Taking into account the reduced baseline allergen PC20, the post-salbutamol allergen PC20 was almost 2 doubling doses (1.94 [1.43], p < 0.01) lower during salbutamol treatment. Thus, 2 weeks of regular inhaled salbutamol increased airway responsiveness to allergen but not to methacholine, and caused tolerance to the protective effect of salbutamol on bronchoconstriction induced by both stimuli. These effects of inhaled beta 2 agonist provide further evidence to support detrimental effects of their regular use. High doses of inhaled salbutamol produce substantial improvements in airway response in patients with asthma, and are associated with dose-dependent systemic beta-adrenoceptor responses. The purpose of the present study was to investigate whether tachyphylaxis occurs during prolonged treatment with high dose inhaled salbutamol. Twelve asthmatic patients (FEV1, 81 +/- 4% predicted), requiring only occasional inhaled beta-agonists as their sole therapy, were given a 14-day treatment with high dose inhaled salbutamol (HDS), 4,000 micrograms daily, low dose inhaled salbutamol (LDS), 800 micrograms daily, or placebo (PI) by metered-dose inhaler in a double-blind, randomized crossover design. During the 14-day run-in and during washout periods, inhaled beta-agonists were withheld and ipratropium bromide was substituted for rescue purposes. At the end of each 14-day treatment, a dose-response curve (DRC) was performed, and airway (FEV1, FEF25-75) chronotropic (HR), tremor, and metabolic (K, Glu) responses were measured at each step (from 100 to 4,000 micrograms). Treatment had no significant effect on baseline values. There were dose-dependent increases in FEV1 and FEF25-75 (p less than 0.001), and pretreatment with HDS did not displace the DRC to the right. DRC for HR (p less than 0.001), K (p less than 0.001), and Glu (p less than 0.005) were attenuated after treatment with HDS compared with PI. There were also differences between HDS and LDS for HR (p less than 0.001) and Glu (p less than 0.05) responses. Frequency and severity of subjective adverse effects were also reduced after HDS: tremor (p less than 0.001), palpitations (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS) Pretreatment with inhaled beta 2-agonists is often recommended for the prevention of exercise-induced bronchoconstriction. Regular treatment with inhaled beta 2-agonists has been associated with worsened baseline airway caliber and increased airway responsiveness. In this study, we have investigated the effects of regular inhaled albuterol on the severity of exercise-induced bronchoconstriction using a double-blind, placebo-controlled, randomized, crossover design. Ten subjects inhaled either albuterol or placebo (2 x 100 micrograms, four times per day) for 7 d. On the eighth and ninth days of treatment periods, subjects performed 5-min constant work rate cycle ergometry exercise challenges after inhaling 200 micrograms of placebo (eighth day) or albuterol (ninth day). Forced expired volume in 1 s (FEV1) was measured on arrival in the laboratory as well as before and for 1 h after exercise. One week of regular inhaled albuterol compared with placebo resulted in: (1) a lower baseline FEV1 (mean difference, 230 ml) (p = 0.02); (2) a lower minimum postexercises FEV1 without inhaled albuterol pretreatment (mean difference, 390 ml; range, -50 ml to 1,250 ml) (p = 0.01); (3) a lower minimum postexercise FEV1 with inhaled albuterol pretreatment (p < 0.01). The smallest degree of exercise-induced bronchoconstriction occurred after a week of regular placebo and pretreatment with inhaled albuterol immediately before exercise. Inhalation of albuterol four times daily for 1 wk worsens exercise-induced bronchoconstriction; however, it remains extremely effective when used immediately before exercise for preventing bronchoconstriction. To compare the long-term efficacy and safety of albuterol administration using a Spiros Inhalation System (Dura Pharmaceuticals; San Diego, CA) dry powder inhaler (DPI) and albuterol (Ventolin; Glaxo Wellcome; Research Triangle Park, NC) administration using a metered-dose inhaler (MDI) in patients with asthma.
                This was a phase III, 12-week, randomized, double-blind, double-dummy, placebo-controlled, parallel-group, multicenter study of 283 adolescent and adult patients with mild to moderate asthma. The patients were randomized into one of three treatment groups: the Spiros group, who were given 108 microg/actuation of albuterol sulfate equivalent to 90 microg of albuterol base; the MDI group, who were given 90 microg/actuation of albuterol; and the placebo group.
                Over the length of the study, the Spiros and MDI groups were comparable in all FEV1 parameters. Both active treatment groups were superior to the placebo group for each FEV1 parameter at all visits. With the exception of differences at treatment week 0 for the maximum percent change in the FEV1, the duration of effect, and the area under the curve at baseline, there were no statistically significant differences between the Spiros and MDI groups for any FEV1 parameters. Using a repeated-measures analysis, the FEV1 parameters at week 0 for the Spiros group were not statistically significantly different from the parameters at weeks 4, 8, and 12. The same analysis effect at week 0 for the MDI group was greater for maximum percent change in the FEV1 from baseline (weeks 4, 8, and 12) and duration of effect. Adverse events and changes in clinical laboratory values, vital signs, ECG results, and physical examinations were reported with similar incidence in each of the three treatment groups.
                Both active treatments were superior to the placebo treatment. The Spiros DPI was well tolerated and was as effective as the albuterol MDI in treating patients with moderate asthma. Although many asthmatic patients are treated with a combination of beta2 agonist and corticosteroid inhalers, the clinical effects of combining the drugs are unknown. Studies on the early asthmatic response to allergen suggest that beta2 agonists may reduce the benefit of inhaled corticosteroids. A study of the effects of combining the drugs on asthma control was undertaken.
                Sixty one subjects with mild to moderate asthma were randomised to a double blind crossover comparison of inhaled budesonide (200-400 microg twice daily), terbutaline (500-1000 microg four times daily), combined treatment, and placebo. Each treatment was given for six weeks following a four week washout period. Ipratropium was used for symptom relief. Treatments were ranked from worst (1) to best (4) based on need for oral steroid, mean morning peak flow, nocturnal awakening, ipratropium use, and asthma symptoms. Lung function and bronchial hyperresponsiveness were measured before and after each treatment.
                Evaluable data for all four treatments were obtained from 47 subjects. The mean rank of each treatment was: placebo = 2.05; terbutaline = 2.13; budesonide = 2.48; combined treatment = 3.34. Combined treatment was ranked significantly better than any other treatment (p<0.01). Mean (95% CI) morning and evening peak flows were 14 (5 to 23) and 24 (15 to 34) l/min higher, respectively, during combined treatment than during budesonide, and 27 (17 to 37) and 15 (7 to 23) l/min higher than during terbutaline. Asthma symptoms tended to be least frequent during combined treatment but were not significantly different from budesonide alone. There was no significant difference between combined treatment and budesonide alone for lung function and bronchial hyperresponsiveness.
                In this group of mild to moderate asthmatic subjects the combination of beta2 agonist and corticosteroid gave better asthma control than either treatment alone. There was no evidence that regular beta2 agonist treatment impaired the beneficial effect of inhaled corticosteroid. Salbutamol is frequently used as a bronchodilator for infants who wheeze. Many single dose studies have questioned its effectiveness.
                To investigate the response of wheezy infants to salbutamol over an extended time period in order to elucidate either symptomatic relief or a protective effect.
                Eighty infants under 1 year, with persistent or recurrent wheeze and a personal or family history of atopy, were recruited to a randomised, double blind, cross over, placebo controlled trial. Salbutamol (200 microg three times daily) or placebo were administered regularly over two consecutive treatment periods of four weeks via a spacer and mask. Symptoms of wheeze and cough were recorded in a diary. At the end of the study pulmonary function tests were performed before and after salbutamol (400 microg).
                Forty eight infants completed the diary study; 40 infants underwent pulmonary function testing. No difference in mean daily symptom score was observed between the salbutamol and placebo periods. There was no difference in the number of symptom free days. Compliance and forced expiratory flows remained unchanged and resistance increased following salbutamol. There was no relation between the response measured by symptom score or pulmonary function in individual patients.
                In wheezy infants with an atopic background, there was no significant beneficial effect of salbutamol on either clinical symptoms or pulmonary function. Clinical effects could not be predicted from pulmonary function tests. Salbutamol cannot be recommended as the bronchodilator of choice in this age group. Formoterol is a beta2-adrenergic agent which, when inhaled, produces rapid and long-lasting bronchodilatation.
                The aim of this study was to compare the efficacy, safety, and tolerability of formoterol powder for inhalation delivered via the Aerolizer device with placebo and with albuterol delivered via metered-dose inhaler in patients with mild to moderate persistent asthma.
                In a multicenter, double-blind, parallel-group study, 541 patients were randomized at 26 trial sites to receive either formoterol, 12 microg twice daily; formoterol, 24 microg twice daily; albuterol, 180 microg four times daily; or a placebo for 12 weeks. The effects of each treatment on lung function, asthma symptoms, and frequency of rescue albuterol use were evaluated. Adverse effects and clinical laboratory parameters were also evaluated.
                The bronchodilatory effects of formoterol were rapid in onset and persisted for 12 hours. Both formoterol doses were more effective than placebo and albuterol for objective measures of lung function. Morning and evening peak expiratory flow rates were more improved with formoterol, and formoterol provided significantly greater improvements in asthma symptom scores compared with both albuterol and placebo. Overall, patients taking formoterol used significantly less rescue medication than did those taking albuterol or placebo. Nocturnal awakenings occurred less often with formoterol than with placebo or albuterol. The therapeutic effects of formoterol were maintained over the entire 12 weeks of treatment. Adverse events were similar for all treatment groups, and clinical laboratory data were unremarkable.
                Rapid-onset, long-acting formoterol, administered via the Aerolizer inhaler, is an effective and safe treatment for patients with mild to moderate persistent asthma. The effect of regular inhaled beta-agonist on the treatment of exercise-induced bronchoconstriction was studied. Eight subjects with exercise-induced bronchoconstriction took 1 week each of salbutamol 200 microg qid or placebo in a random-order, double-blind, crossover study. They then withheld this treatment for 8 hours before performing a dry-air, sub-maximal exercise challenge at a work-rate previously shown to induce a 15% fall in forced expiratory volume in 1 second (FEV1). Five minutes after exercise, they inhaled salbutamol 100, 100, and 200 microg at 5-minute intervals. The mean pre-exercise FEV1 was similar on both study days. However, pretreatment for 1 week with salbutamol led to a significantly greater fall in FEV1 after exercise. The FEV1 remained lower than during the placebo arm despite the administration of salbutamol after exercise. This difference persisted 25 minutes after exercise. It is concluded that regular beta-agonist treatment leads to increased exercise-induced bronchoconstriction and a suboptimal bronchodilator response to beta-agonist. The data suggest that previous regular beta-agonist treatment may lead to a failure to respond to emergency bronchodilator treatment during an acute asthma attack and support current opinion that regular short-acting beta-agonist therapy should not be used to treat asthma. It has been suggested that regular treatment with high doses of beta 2-agonists might result in poorer control of asthma and increased bronchial responsiveness. We have examined change in FEV1 (delta FEV1), bronchial reactivity, peak expiratory flow (PEF), and symptoms during and after 3 wk of regular treatment with a relatively low dose of albuterol and broxaterol, a new beta 2-agonist. Eleven subjects 18 to 50 yr of age with mild asthma inhaled albuterol (200 micrograms), broxaterol (400 micrograms), or placebo three times a day for 3 wk with a 2- to 4-wk run-in/washout period between treatments. Ipratropium bromide was allowed for symptomatic relief. The PD20 (dose of histamine causing a 20% fall in FEV1) was measured before and 11, 35, and 59 h after cessation of treatment and a bronchodilator dose-response study before and 83 h after cessation of treatment. Change from baseline after albuterol and broxaterol are compared with change after placebo. Diurnal change in PEF (amplitude % mean) increased during treatment with albuterol by 6.5% (95% CI, 1.7-12.3; p < 0.02) mainly because of a fall in morning PEF. Cessation of treatment with both beta 2-agonists was associated with a fall in FEV1 and PD20 compared with placebo.(ABSTRACT TRUNCATED AT 250 WORDS) This study compared the efficacy of a low dose of formoterol Turbuhaler 6 micrograms b.i.d. (F) with that of terbutaline 0.5 mg q.i.d. (T), and placebo (P) from Turbuhaler. After a 2-week run-in, 397 adults with mild to moderate asthma were randomly allocated to one of the treatments for 12 weeks. During run-in, the mean morning peak expiratory flow (PEF) was 360 (F), 368 (T) and 367 1 min-1 (P). F was better than T (P = 0.014) and P (P = 0.0001) in improving morning PEF [mean changes from run-in: 20 (F), 9 (T), and 21 min-1 (P)]. F was statistically significantly more effective than either T or P in reducing asthma symptoms. F gave also statistically significantly higher evening PEF and less use of rescue medication than P. Bronchodilator response to study drugs and additional 1.25 mg terbutaline was similar before and after the 12-week treatment period. There were no adverse effects of clinical relevance. In conclusion, formoterol Turbuhaler, 6 micrograms b.i.d. was more effective in improving PEF and offered better asthma control than either terbutaline Turbuhaler, 0.5 mg q.i.d. or placebo. Regular use of formoterol did not reduce the bronchodilator response to additional terbutaline. There were no clinically relevant adverse effects. Recent studies have suggested that regular use of inhaled beta 2 agonists cause loss of asthma control as measured by worsening peak-flow rates, increased asthma symptoms, and more frequent need for supplementary bronchodilators. However, the magnitude of this effect and the reliability of investigator-originated definitions of control is unknown. We studied 341 people with asthma in a four-week, randomised, crossover trial of regular salbutamol (2 puffs--200 micrograms--four times daily) for two weeks and as needed for two weeks. There were no significant differences in morning and evening peak-flow rates between treatments but asthma symptoms and supplementary bronchodilator use were significantly less frequent when salbutamol was given regularly. Asthma episodes occurred 1.39 (1.52) times per day during regular treatment and 2.44 (1.75) times per day during as-needed treatment (p < 0.0001) and 0.50 (0.56) vs 0.65 (0.66) times per night (p < 0.0001). Daytime use of supplementary salbutamol was 1.14 (1.40) vs 2.35 (1.71) puffs per day, (p < 0.0001); night-time use was 0.45 (0.55) vs 0.64 (0.66) puffs per night (p < 0.0001). When control endpoints were compared between treatment periods for each individual by two blinded investigators and control judged by six different sets of criteria, in 70 asthmatics there was no difference in symptom control between periods but in the remainder, control was achieved more often by regular than by as-needed salbutamol (166 vs 69, p < 0.0001). In asthma of moderate severity, regularly administered salbutamol does not produce lower peak flow rates than as-needed salbutamol and is associated with less frequent asthma symptoms. We compared the effects of salmeterol (Sm) (50 micrograms twice daily) with that of salbutamol (Sb) (200 micrograms four times daily) and placebo (P) in patients with mild-to-moderate asthma with asthma symptoms and related the effectiveness of these therapies between patients who used concurrent inhaled corticosteroids (ICS) and those who did not. The study was a 12-wk, multicenter, double-blind, placebo-controlled crossover trial with 367 adult asthmatics randomized to each trial medication for 4 wk. Inhaled Sb was provided as rescue medication to all patients throughout the trial. Only 80% of patients, albeit the majority, were receiving maintenance treatment with ICS throughout this trial; this reflects practice current in early 1990. Each study day, patients recorded their morning and evening peak expiratory flows (PEF), assessment of asthma symptoms, and use of rescue medication. Both morning and evening PEF were greater during treatment with Sm than with Sb (mean differences between the treatments of 29.8 and 14.3 L/min, respectively) or P (27.7 and 20.3 L/min, respectively) (p < 0.0001). Sm was also more effective than Sb or P in lowering diurnal variation in PEF and increasing the percentage of symptom-free days and rescue-free days and nights with no sleep disturbance (p < or = 0.0004). Sb was more effective than P in increasing evening PEF and the percentage of symptom-free days (p < 0.05) and rescue-free days (p < 0.0001). The same clinical superiority of Sm compared with Sb and P was observed in those patients using ICS (p < 0.001 for all treatment comparisons), and to a greater extent than in those patients not using ICS (i.e., Sm was more effective than Sb and P in just six of the 20 treatment comparisons; p < 0.05). In conclusion, Sm 50 micrograms twice daily is effective in the management of mild-to-moderate asthma and it further improves asthma control in patients already using ICS. Seventeen asthmatic patients were allocated at random to one of two treatment regimens: prophylactic (10 patients), in which salbutamol inhaler was used regularly in a dose of 200 micrograms 4-times daily; or symptomatic (7 patients), in which a placebo inhaler was used regularly as 2 actuations 4-times daily. In both regimens, an 'escape' salbutamol inhaler was given to be used for symptomatic relief if and when needed. The study lasted 12 months, after a run-in period of 1 month to accustom patients to the trial procedure. At the end of the year, 16 patients transferred to the alternative regimen for a further 3 months. Both groups were well matched except that the group starting with the prophylactic regimen had more severe airways obstruction than the symptomatic group. Patients were assessed by daily scores of their asthmatic symptoms, twice daily PEFR measurements and the amount of anti-asthmatic medication used. Acute reversibility tests were performed every month at the clinic visits. Patients treated prophylactically had less seasonal variation in PEFR and generally lower symptom scores despite a lower mean PEFR. There was no evidence to suggest tolerance was developing either by acute reversibility tests or by an escalating use of symptomatic salbutamol or other anti-asthma medication. The prophylactic use of salbutamol seemed to provide a more stable control of asthma, offering potential benefit to patients. The aim of this study was to compare the effect of regular versus intermittent (p.r.n.) bronchodilators on bronchial reactivity and asthma control in patients on concomitant inhaled corticosteroids. We studied 12 patients with asthma in a prospective, randomised, single-blind, single-dummy, three-period crossover trial comparing placebo (2 puffs t.d.s.), salbutamol (200 micrograms t.d.s.) and oxitropium bromide (200 micrograms t.d.s.) for 28 days each. Computerised spirometry and bronchial reactivity to histamine were obtained on entry and after each treatment period. Symptom scores, use of rescue bronchodilator and peak expiratory flow rates were recorded daily. There were no significant differences in bronchial hyperreactivity between the salbutamol, oxitropium and placebo treatment periods. There were no significant differences in baseline FEV1, FEF25-75%, symptom scores, use of rescue bronchodilator or morning and evening PEFR between treatment periods. Intermittent beta agonist therapy is as effective as regular therapy in terms of asthma control and bronchial hyperreactivity in patients on concomitant inhaled corticosteroid therapy. Since intermittent therapy achieves similar results with significantly lower beta agonist consumption, the data support current recommendations that beta agonists should be taken on a p.r.n. basis in asthma patients on inhaled steroids. Inhaled beta-agonists are the most commonly used treatment for asthma, but data suggest that regularly scheduled use of these agents may have deleterious effect on the control of asthma. We compared the effects of regularly scheduled use of inhaled albuterol with those of albuterol used only as needed in patients with mild chronic, stable asthma.
                In a multicenter, double-blind study, we randomly assigned 255 patients with mild asthma to inhale albuterol either on a regular schedule (126 patients) or only as needed (129 patients). The patients were followed for 16 weeks.
                The primary outcome indicator, peak expiratory air flow measured in the morning, did not change significantly during the treatment period in the scheduled (416 liters per minute after the run-in period and 414 liters per minute after the treatment period) or the as-needed (424 liters per minute at both times) treatment groups (P=0.71). There were no significant differences between the two groups in peak flow variability, forced expiratory volume in one second, the number of puffs of supplemental albuterol needed, asthma symptoms, asthma quality-of-life score, or airway responsiveness to methacholine. The statistically significant differences between the groups in evening peak flow and in the short-term bronchodilator response to inhaled albuterol were small and judged to be clinically unimportant.
                In patients with mild asthma, neither deleterious nor beneficial effects derived from the regular use of inhaled albuterol beyond those derived from use of the drug as needed. Inhaled albuterol should be prescribed for patients with mild asthma on an as-needed basis. Adult, nonsmoking patients with mild to moderate asthma were randomized to receive 4 mg nedocromil sodium (n = 13), 200 micrograms albuterol (n = 13), or placebo (n = 12) four times daily for 16 wk in a double-blind, double-dummy protocol. Before and after treatment, patients underwent histamine bronchial provocation, followed by fiberoptic bronchoscopy. Bronchial mucosal biopsy tissue and bronchoalveolar lavage fluid were examined in detail. Daily diary cards were kept by each patient. Compared with baseline, the numbers of total (EG1) and activated (EG2) eosinophils, expressed as cells per square millimeter of bronchial biopsy tissue, decreased after treatment with nedocromil sodium (pretreatment: EG1 = 152.2 +/- 42.5 and EG2 = 143.8 +/- 36.8; post-treatment: EG1 = 115.4 +/- 35.1 and EG2 = 104.9 +/- 31.6) and increased after treatment with albuterol (pretreatment: EG1 = 129.3 +/- 28.0 and EG2 = 127.5 +/- 30.2; post-treatment: EG1 = 238.0 +/- 55.0 and EG2 = 211.4 +/- 50.4). Although the changes between the active treatment groups were significantly different (p < 0.05), no such significant differences were found in eosinophil numbers before and after treatment when comparisons were made between either of the active treatment groups and the placebo group. Although not significant, the changes in concentration of eosinophil cationic protein in bronchoalveolar lavage reflected the changes seen in numbers of activated eosinophils. No treatment differences were detected for mast cell or lymphocyte numbers. There were no statistical differences between treatment groups for clinical findings, with the exception of evening peak flow, which was significantly increased (p < 0.05) in the albuterol group.(ABSTRACT TRUNCATED AT 250 WORDS)
In general, these results support current guidelines, although it has given reassuring evidence against concerns over regular use of inhaled short-acting beta-2 agonists.