to evaluate the dose-effect relationship of a controlled-release theophylline in preschool children , 20 patients with asthma ( mean age 4.8 years , range 2 1/2 to 7 years ) were given three different dose levels ( 13.4 +/- 1.4 , 18.4 +/- 1.6 , and 23.5 +/- 2.0 mg/kg/day , mean +/- sd ) at 12-hour intervals for 2 weeks .
C0039771
theophylline
C0004096
asthma