Twelve months, treatment with inhaled salmeterol in asthmatic patients

Abstract

Salmeterol is a new beta 2-receptor agonist with a prolonged duration of action after inhalation, exceeding 12 h in most patients. We have performed a 12-month open follow-up study on 11 patients with reversible asthma. All patients were given salmeterol inhalations (50 micrograms twice daily). Additional asthma treatment included inhaled corticosteroids in all patients, and oral slow-release theophylline or beta 2-receptor agonists in a minority of patients (3 and 1, respectively). Before salmeterol treatment was initiated and after 3, 6, 9 and 12 months of salmeterol treatment, a cumulative dose-response curve to inhaled salbutamol (100, 300 and 900 micrograms) was performed, and FEV1 measured. We also evaluated the effect of each salbutamol dose on finger tremor, systemic blood pressure and heart rate. Blood tests, including white blood count and electrolytes, were taken at each visit. After salmeterol treatment was initiated, morning FEV1, measured before the morning asthma medication, was significantly improved (p < 0.05). The responsiveness to inhaled salbutamol was not decreased during salmeterol treatment, except in one patient with asthma worsening over the study year. Baseline finger tremor measured before salbutamol dose-response curves, was significantly lower at the 12-month visit than before treatment was initiated (p < 0.05). Effects of salbutamol on systemic blood pressure, heart rate or finger tremor was not significantly changed during salmeterol treatment. We found a successive and significant decrease in blood eosinophils (p < 0.05) during the 12 months of salmeterol treatment, when the patient with asthma worsening was excluded in the analysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Bronchodilator response to salbutamol after chronic dosing with salmeterol or placebo

“…These results are in keeping with those obtained from two previous studies [8,9], both of which also showed no change in salbutamol response after chronic treatment with salmeterol. However, both of these were open studies with no control group.…”

“…However, both of these were open studies with no control group. In one of the studies [8], salmeterol treatment lasted just 2 weeks, whilst in the other [9], the duration of treatment was 12 months. In both of these studies, patients continued using short acting β 2 -agonists as rescue medication.…”

“…Treatment ranging from 2 weeks to 12 months with salmeterol 50 µg b.d. has also demonstrated that responsiveness to inhaled salbutamol was not decreased during or after treatment, suggesting no change in β 2 -receptor sensitivity [8,9] Other published data have, conversely, reported that 4 weeks of treatment with the long-acting β 2 -agonist formoterol, results in tolerance to its acute bronchodilator effects [10] and a recently published study has claimed that continuous exposure to salmeterol 50 µg b.d. results in reduced bronchodilator response to repeated doses of inhaled salbutamol [11].…”

Salmeterol: An inhaled /β2-agonist with prolonged duration of action

“…5a). After the completion of this investigation, we followed the patients in an open study in the same way for 12 months [24]. The dose-effect curve for inhaled salbutamol after 3, 6, 9, and 12 months' treatment showed a well-maintained maximal response without any sign of development of tolerance (Fig.…”

“…No inhibitory effect on the maximal bronchodilator effect was observed after the salmeterol treatment period. Data are shown as FEV\ (% of maximum value for each patient; from[44]); (b) The bronchodilator effect of inhaled salbutamol (100, 300, and 900 J.Lg) before and after 6 and 12 months' treatment with salmeterol (50 J.Lg twice daily), 24 h after the last dose of salmeterol (from[24]). …”