Comparison of the efficacy and systemic effects of 4 mg and 8 mg formulations of salbutamol controlled release in patients with asthma

• Published in: European journal of clinical pharmacology 1990-01, Vol.39 (3), p.281-285
• Main Authors: Lipworth, B J, Clark, R A, Dhillon, D P, Palmer, J B, McDevitt, D G
• Format: Article
• Language: English
• Subjects: Adult; Albuterol - administration & dosage; Albuterol - adverse effects; Albuterol - therapeutic use; Asthma - drug therapy; Delayed-Action Preparations; Dose-Response Relationship, Drug; Double-Blind Method; Drug Administration Schedule; Female; Hemodynamics - drug effects; Humans; Male; Middle Aged; Peak Expiratory Flow Rate - drug effects; Randomized Controlled Trials as Topic; Vital Capacity - drug effects
• ISSN: 0031-6970; 1432-1041
• DOI: 10.1007/BF00315111

The purpose of the present study was to compare the efficacy and systemic effects of 4 mg and 8 mg doses of salbutamol controlled release (SCR) after single dosing and at steady state in patients with asthma. Fifteen asthmatic patients (Age 36 y, FEV1 85% predicted) were given SCR 4 mg and 8 mg twice daily for 7 days in a randomised double-blind cross-over design, with at least 7 days washout between treatments. There were no differences between the bronchodilator effects of 4 mg and 8 mg doses. There was no evidence of tolerance to the bronchodilator effects after chronic dosing. Morning and evening PEFR measurements also showed improvements during treatment with SCR 4 mg and SCR 8 mg, although there were no differences between the two formulations. Both doses of SCR caused significant objective tremor responses which were maintained after chronic dosing. The 8 mg dose produced a larger tremor response after single dosing, but not at steady-state. Subjective tremor occurred in 7 patients with SCR 8 mg, and in 2 patients with SCR 4 mg. There were no cardiac arrhythmias on Holter ECG monitoring. These results suggest that the 8 mg dose of SCR was no more effective than the 4 mg formulation, and was associated with more systemic adverse effects.