Slow-release oral salbutamol and aminophylline in nocturnal asthma: relation of overnight changes in lung function and plasma drug levels

• Published in: Thorax Vol. 35; no. 7; pp. 526 - 530
• Main Authors: Fairfax, A J, McNabb, W R, Davies, H J, Spiro, S G
• Format: Journal Article
• Language: English
• Published: England BMJ Publishing Group Ltd and British Thoracic Society 01-07-1980; BMJ Publishing Group LTD
• Subjects: Adolescent; Adult; Aged; Albuterol - blood; Albuterol - therapeutic use; Aminophylline - therapeutic use; Asthma - blood; Asthma - drug therapy; Chronic Disease; Circadian Rhythm; Clinical Trials as Topic; Delayed-Action Preparations; Double-Blind Method; Female; Humans; Male; Middle Aged; Peak Expiratory Flow Rate; Theophylline - blood
• ISSN: 0040-6376; 1468-3296
• DOI: 10.1136/thx.35.7.526

In a double-blind controlled trial 14 chronic asthmatic patients with regular nocturnal exacerbations took 16 mg slow-release oral salbutamol (two Ventolin spandets), 450 mg slow-release aminophylline (two Phyllocontin Continus tablets), or placebo at midnight. Mean peak expiratory flow rates on waking were significantly higher on the active drugs than on placebo (p < 0.01 for salbutamol; p < 0.05 for aminophylline) but neither drug abolished the overnight fall in PEFR. Plasma drug levels at 0600 hr were 17.3 ng/ml (+/- 5.3 ng/ml SD) for salbutamol, and 7.1 micrograms/ml (+/- 3.1 micrograms/ml SD) for theophylline. Steady-state derived from plasma levels of salbutamol during intravenous infusion indicated that the morning salbutamol levels were probably in a therapeutic range for asthma. The morning theophylline levels, however, were suboptimal when aminophylline was given only at night.