Comparisons of 12-hour and 24-hour sustained-release theophyllines in the management of chronic obstructive pulmonary disease

Lee, Yang Deok; Lee, Heung Bum; Lee, Yong Chul; Rhee, Yang Keun

Abstract

BACKGROUND
Theophylline is a weak bronchodilator with a narrow therapeutic window. Much of its clinical benefit derives from effects other than bronchodilaton; therapeutic doses of theophylline increase ventilatory drive, enhance diaphragmatic contractility and increase cardiac output. About 20% of COPD patients respond to theophylline with improved airflow, exercise tolerance and quality of life. Generally it is prescribed as a twice-daily equal-dose regimen so as to produce nearly constant blood level throughout each 24 hour. We compared 12-hour and 24-hour sustained-release theophyllines in the management of chronic obstructive pulmonary disease.
METHODS
A crossover study was conducted with 27 adult chronic obstructive pulmonary disease requiring daily bronchodilator therapy. The study group included nineteen males and eight females ranging in age from 48 to 71 years. The overall approach was to place the patients first on the twice-daily preparation (Etheophyl(R)) for 28 days at 8 AM and 8 PM and pulmonary function tests and theophylline level were measured on the 28th day. The patients were subsequently switched to the once-daily preparation (Uniphyl(R)) in the same daily dose at 8 PM on the 29th day and the same parameters were measured on the 56th day.
RESULTS
The mean serum levels of theophylline were 8.80+/-2.64 microgram/mL in the Etheophyl(R)-treated and 8.48+/-2.08 microgram/mL in the Uniphyl(R)-treated period. And the FEV1 showed 63.72+/-8.63% in the Etheophyl(R)-treated and 62.81+/-9.81% in the Uniphyl(R)-treated period.
CONCLUSION
The results suggested that there was little clinical differences between the two medications. The two drugs were equally effective in clinically controlling COPD over the four weeks of treatment.