two controlled-release theophylline drugs , t-d ( theo-dur tablets ) administered 12-hourly , and preparation u ( uniphyl tablets ) once daily , given in 7-day sequences in daily 800-mg doses , produced comparable steady-state serum profiles in nonsmoking adults with asthma , chronic bronchitis , or both , showing acceptable theophylline clearances .
C0004096
asthma
C0039771
theophylline