Combination therapy of theophylline and terbutaline as sustained-release preparations in patients with asthmatic bronchitis.

In a group of ten patients with chronic asthmatic bronchitis, the effect of monotherapy with theophylline and terbutaline and the combination of both drugs, as sustained-release tablets, was compared to placebo, in a double-blind cross-over, triple dummy at random study. Lung function parameters, tremor measurements, c-AMP plasma levels, theophylline- and terbutaline-plasma levels were determinated. Monotherapy with theophylline and terbutaline in a relatively low dosage achieved a good lung function improvement without severe side effects, as compared to placebo. The combination of both drugs in the same dosage achieved a statistically significant enhancement of the lung function improvement, as compared to monotherapy, without an increase of side effects. An additional effect of theophylline and terbutaline on bronchodilation is demonstrated.